I filed my 2021 taxes and had to do admendment, which I printed and sent it via US Mail. I still have not recieved it and its pending How can I view my 2021 tax file?

You did not mention how long ago you mailed the amended return.   It can take the IRS 4 - 6 months to process an amended return--do not expect quick results when you amend.

You can watch for information here:

https://www.irs.gov/Filing/Individuals/Amended-Returns-(Form-1040-X)/Wheres-My-Amended-Return-1