how to use trigger process between three tables in sql server

Complete process to use trigger
create table adminassign
(
Com_name Varchar(50),
pm_name Varchar(50),
Project_code int,
Email_id Varchar(50),
Received_date varchar(50),
Deadline  varchar(50),
Project_status varchar(50),
Expected_date varchar(50),
Source_language varchar(50),
Target_language varchar(50),
Volume_project varchar(50),
Job_type Varchar(50),
File_attached varchar(200),
Instruction_file  varchar(200)
)
Ven_assign
create table ven_assign
(
Com_name Varchar(50),
pm_name Varchar(50),
Project_code int,
Email_id Varchar(50),
Received_date varchar(50),
Deadline  varchar(50),
Project_status varchar(50),
Expected_date varchar(50),
Source_language varchar(50),
Target_language varchar(50),
Volume_project varchar(50),
Job_type Varchar(50),
File_attached varchar(200),
Instruction_file  varchar(200)
)
Project_id
create table project_id
(
Com_name Varchar(50),
pm_name Varchar(50),
Project_code int,
Email_id Varchar(50),
Received_date varchar(50),
Deadline  varchar(50),
Project_status varchar(50),
Expected_date varchar(50),
Source_language varchar(50),
Target_language varchar(50),
Volume_project varchar(50),
Job_type Varchar(50),
File_attached varchar(200),
Instruction_file  varchar(200)
)
assign_prcocreate table assign_prco
(
Com_name Varchar(50),
pm_name Varchar(50),
Project_code int,
Email_id Varchar(50),
Received_date varchar(50),
Deadline  varchar(50),
Project_status varchar(50),
Expected_date varchar(50),
Source_language varchar(50),
Target_language varchar(50),
Volume_project varchar(50),
Job_type Varchar(50),
File_attached varchar(200),
Instruction_file  varchar(200)
)
Trigger Ven_assign
create trigger Venassigntrigger
on Ven_assign
for
Insert as
declare @Com_name Varchar(50)
declare @pm_name Varchar(50),
declare @Project_code int,
declare @Email_id Varchar(50),
declare @Received_date varchar(50),
declare @Deadline  varchar(50),
declare @Project_status varchar(50),
declare @Expected_date varchar(50),
declare @Source_language varchar(50),
declare @Target_language varchar(50),
declare @Volume_project varchar(50),
declare @Job_type Varchar(50),
declare @File_attached varchar(200),
declare @Instruction_file  varchar(200)
select @Com_name=Com_name from inserted
select @pm_name=pm_name from inserted
select @Project_code =Project_code  from inserted
select @Email_id=Email_id from inserted
select @Received_date=Received_date from inserted
select @Deadline=Deadline from inserted
select @Project_status=Project_status from inserted
select @Expected_date=Expected_date from inserted
select @Source_language=Source_language from inserted
select @Target_language=Target_language from inserted
select @Volume_project=Volume_project from inserted
select @Job_type=Job_type from inserted
select @File_attached=File_attached from inserted
select @Instruction_file=Instruction_file from inserted
begin
insert adminassign values(+@Com_name,@pm_name,@Project_code, @Email_id,@Received_date,@Deadline,@Project_status,@Expected_date, @Source_language, @Target_language,@Volume_project,@Job_type, @File_attached,@Instruction_file)
end
trigger project_idcreate trigger project_idtrigger
on project_id
for
Insert as
declare @Com_name Varchar(50)
declare @pm_name Varchar(50),
declare @Project_code int,
declare @Email_id Varchar(50),
declare @Received_date varchar(50),
declare @Deadline  varchar(50),
declare @Project_status varchar(50),
declare @Expected_date varchar(50),
declare @Source_language varchar(50),
declare @Target_language varchar(50),
declare @Volume_project varchar(50),
declare @Job_type Varchar(50),
declare @File_attached varchar(200),
declare @Instruction_file  varchar(200)
select @Com_name=Com_name from inserted
select @pm_name=pm_name from inserted
select @Project_code =Project_code  from inserted
select @Email_id=Email_id from inserted
select @Received_date=Received_date from inserted
select @Deadline=Deadline from inserted
select @Project_status=Project_status from inserted
select @Expected_date=Expected_date from inserted
select @Source_language=Source_language from inserted
select @Target_language=Target_language from inserted
select @Volume_project=Volume_project from inserted
select @Job_type=Job_type from inserted
select @File_attached=File_attached from inserted
select @Instruction_file=Instruction_file from inserted
begin
insert adminassign values(+@Com_name,@pm_name,@Project_code, @Email_id,@Received_date,@Deadline,@Project_status,@Expected_date, @Source_language, @Target_language,@Volume_project,@Job_type, @File_attached,@Instruction_file)
end
 trigger assign_prcocreate trigger assign_prcotrigger
on assign_prco
for
Insert as
declare @Com_name Varchar(50)
declare @pm_name Varchar(50),
declare @Project_code int,
declare @Email_id Varchar(50),
declare @Received_date varchar(50),
declare @Deadline  varchar(50),
declare @Project_status varchar(50),
declare @Expected_date varchar(50),
declare @Source_language varchar(50),
declare @Target_language varchar(50),
declare @Volume_project varchar(50),
declare @Job_type Varchar(50),
declare @File_attached varchar(200),
declare @Instruction_file  varchar(200)
select @Com_name=Com_name from inserted
select @pm_name=pm_name from inserted
select @Project_code =Project_code  from inserted
select @Email_id=Email_id from inserted
select @Received_date=Received_date from inserted
select @Deadline=Deadline from inserted
select @Project_status=Project_status from inserted
select @Expected_date=Expected_date from inserted
select @Source_language=Source_language from inserted
select @Target_language=Target_language from inserted
select @Volume_project=Volume_project from inserted
select @Job_type=Job_type from inserted
select @File_attached=File_attached from inserted
select @Instruction_file=Instruction_file from inserted
begin
insert adminassign values(+@Com_name,@pm_name,@Project_code, @Email_id,@Received_date,@Deadline,@Project_status,@Expected_date, @Source_language, @Target_language,@Volume_project,@Job_type, @File_attached,@Instruction_file)
end
Complete trigger process
for use primary key/
create table assign_prco
(
Project_code int primary key,
Com_name Varchar(50),
pm_name Varchar(50),
Email_id Varchar(50),
Received_date varchar(50),
Deadline  varchar(50),
Project_status varchar(50),
Expected_date varchar(50),
Source_language varchar(50),
Target_language varchar(50),
Volume_project varchar(50),
Job_type Varchar(50),
File_attached varchar(200),
Instruction_file  varchar(200)
)