It depends. First, if you need your adjusted gross income from your 2023 tax return and you didn't file it, the number would be zero. If you did file it you can get an IRS Transcript (click the link to sign up or sign in).
Next, if you didn't file a 2023 tax return or you need to amend it you can do that using one of the links below.
You can file your 2024 tax return and include your self employment for that tax year using the information in the link below.