Sometimes the search function here works, sometime it doesn't.  Today it did:

https://accountants.intuit.com/support/en-us/help-article/amend-tax-return/amending-individual-retur...

For the record, they say to make a copy of the file to do the amendment.  Personally, I never do but I always keep a paper copy of the returns so that that I leave footprints for myself.