M-MTax
Level 12

Deductions & credits

I'm in my mid-70's and I'm stone broke. in 2020 I decided to start selling my books and record collections online

You should check out the VITA and TCE programs......

https://www.irs.gov/individuals/free-tax-return-preparation-for-qualifying-taxpayers

IGNORE the advice about your "inventory" since it sounds like you're just selling off your personal items that you've collected over the years......that's NOT inventory and you DON'T have a business. What you have are....at most.....capital gains from selling your personal possessions.