I wasn’t able to file my extension online, so it will be my first time filing through mail. I only have my W-2’s. Is that all I need and how do I mail them?

not filing your extension online does not prevent you from e-filing your return.  as a matter of fact even if you did not file a 2024 extension you should still be able to e-file 2024

E-filing for 2024 returns is available until October 15, 2025.  If you are getting a refund or do not owe, not filing an extension will not matter.  If you owe tax due, then you will be subject to late filing penalties and interest for which the IRS will bill you; TurboTax will not calculate those.