How can I stop my taxes from being done after being approved

Once you have submitted your tax returns, and they have been accepted, you cannot "stop" them.  Your only option would be to file an amended return.  To amend your return, see:

How do I amend my 2019 TurboTax Online return?

Amending will be possible after March 25. See how to do 2020 here

https://ttlc.intuit.com/community/amending/help/how-do-i-amend-my-return/01/27439