Newbie Needs Help With @@identity

I have a form that submits to multiple tables.  After insertion into the first table I need to access the identity key from the record and use is to associate a record in another table.  The form element I'm inserting into the second table however, is not a required field so I think I need to check IS NOT NULL first.  In my code below I have copied the insert statement for the first table and the conditional and subsequent insert into the 2nd table.  I am uncertain where and how I get and use @@identity.  The error I'm getting when I run the Check Syntax button is: 'incorrect syntax near @@identity.'
I appreciate someone telling me how to correct my syntax.
 
INSERT INTO GPRA_Activities
(
SubmitDate,
StaffId,
GPRAId,
FreedomID,
DocumentDesc,
ActivityTitle,
ActivityDesc


)
VALUES
(
getDate(),
@StaffId,
@GPRAId,
@FreedomID,
@DocumentDesc,
@ActivityTitle,
@ActivityDesc

SELECT @@identity
)



if @KeywordId1 IS NOT NULL

    @@identity smallint,
   
    INSERT INTO GPRA_KeywordsUsed
    (
    ActivityId,
    KeywordId
    )
    VALUES
    (
    @@identity,
    @KeywordId1   
    )

GO