Amend return before October 2021 because of excess Roth IRA contributions in 2020

Hi,

 

I contributed to a Roth IRA in 2020 (and in 2021) when I shouldn't have done so because of income limits. My financial institution computed the realized gains and now I need to amend my 2020 return to reflect this. I have several questions about how to make this in practice:

 

1. How do I amend the return using TurboTax (that I used to prepare the return originally) to reflect this specific change? My financial institution said they would send a 1099-R in January 2021 but I think I need to amend the return now, or not?

2. It is my understanding that as long as I do this before October, the 6% penalty wouldn't apply. Is this the case? Is this something TurboTax will take into account?

3. What about the 2021 excess contributions? Should I simply wait until it's time to prepare the tax return next year?

Thanks.