You'll need to include your W-2s and some types of Form 1099, among other things.
According to Assembling Your PA-40 in the PA-40 Instructions Booklet, you should include your:
Federal Forms, W-2, 1099-R, 1099-MISC, 1099-NEC. Photocopies of your Form(s) W-2 (be sure the information is legible), or your actual Form(s) W-2. Include a statement to list and total your other taxable compensation. You must submit photocopies of your Form(s) 1099-R, 1099-MISC, 1099-NEC and other statements that show other compensation and any PA tax withheld.
NOTE: Do not include copies of Form(s) 1099-DIV and 1099-INT, unless the forms show PA income tax withheld
See the link above for a listing of all the documents you need to include with your state return.
