Where does it ask for the total values of all my Traditional IRA(s) as of 12/31/2020? It's not under the typical IRA stuff. Where do I find it exactly?

It will be in the 1099-R section:

1. Login to your TurboTax Account 
2. Click on "Search" on the top right and type “1099-R”
3. Click on “Jump to 1099-R”
4. On the "Your 1099-R Entries" screen click "continue"
5. Answer "yes" to "Any nondeductible Contributions to your IRA?" if you had any nondeductible contributions in prior years.
6. Enter the basis
7. Enter the value on the "Tell Us the Value of Your Traditional IRA" screen

In https://ttlc.intuit.com/community/taxes/discussion/re-input-12-31-2019-value-of-ira-s/01/1199080 folks suggest that there are cases where TT needs those values, namely "to determine the penalty if you have an excess contribution in a Traditional IRA or to calculate the taxable amount of a traditional IRA distribution or Roth conversion made in if you have basis in nondeductible traditional IRA contributions."

This explains how to get back to those questions:

https://ttlc.intuit.com/community/retirement/discussion/where-do-i-enter-the-2018-year-end-value-for-my-traditional-ira-this-is-needed-to-calculate-the-2018/00/169651

Thank you  so much! BTW, I'm doing this as part of an amended return. Are the instructions on how to get there and what to do any different if you are doing an amended return?

Also, I don't believe I got a 1099-R. I didn't have any distributions, rollovers. I was in Turbo Tax when the information I put in told me I had over contributed to my traditional IRA in 2020. So if I put yes I did get a 1099-R, it might get me to the right page, but it's not a true answer. What should I do?