I can’t find my w-2. I never received a paper copy of it, and my ex employer switched from paychex, to heartland right when i quit so i can’t access my w-2 anywhere.

You employer is required to provide you with a copy of your W-2 by the end of January.  Contact your employer and have them provide you the W-2 or how to access your W-2 from their payment provider.

An alternative is to file an extension immediately, then ask for a transcript of your account at the IRS. You'll want the Wage and Income Transcript, which you may be able to get online. Your employer should have sent a copy of your W-2 to the IRS (just like your employer was supposed to send you a copy by January 31st, as Don said).

This is a lot of work and may or may not work, so do what Don suggested, but use the Transcript as fallback.