If I accidentally didn't send in my taxes last year. I thought I was done with it and submitted it. Now it's gone. Is there a backup in the system?

The 2022 return you prepared will be in your account.  But it cannot be e-filed now.  The only way to file it is by mail.   E-filing is permanently closed for 2022 returns.  You can print it, sign and date it in ink, and mail it.

https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/01/27010

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.

Federal and state returns must be in separate envelopes and they are mailed to different addresses.  Read the mailing instructions that print with your tax return carefully so you mail them to the right addresses.