I need file iso Access2021_R_retail

Very strange. Why does it so heavy - 4.2 Gb?
Office 2021 Pro Plus has 4.0 Gb.

https://officecdn.microsoft.com/db/492350F6-3A01-4F97-B9C0-C7C6DDF67D60/media/en-US/Access2021Retail.img

I don't use Office Retail.

Maybe I was mistaken, for such kind of installation you need to use Office 2021 Pro Plus Retail activation key.

Thank you very much

Not sure, you can find it. 
Use Office 2013-2021 C2R Install 7.3.9 
 
Set up Microsoft Office 2021, bitness, language and tick Access only. Press Install Office. Don"t convert to VL.
Don"t forget to disable AV (Defender) before you download and start.