I need to get a copy of my 2021 tax return. My ex husband has the account that the taxes were done in and I need access to my 2021 return.

[xmasbaby0]

Unless your "ex" gives you the information to access the account and the user ID, you will not be able to get into the account.   Ask him for a copy of the return, or get your attorney involved if he will not cooperate.  You are entitled to a copy of a joint tax return that has your name on it.

Or...seek a copy from the IRS:

 You can get a free transcript from the IRS or for a fee of $30 an actual copy of your tax return.

https://www.irs.gov/individuals/get-transcript

https://www.irs.gov/pub/irs-pdf/f4506.pdf