Capital Gains Tax on Sale of Primary residence

I bought my first townhouse (new house) in July 2016 and lived there till July 2023, in Redmond Washington. I bought and moved to my second house in July 2023 and sold the first townhouse in August 2023 for $1.07M. The total cost of the townhouse is $591K including the upgrades down by the builder.  I paid $22,892 capital gain tax to IRS in December 2023. 

My questions are:

1. Is it correct to use 15% tax rates for this transaction?

2. What support do I need as the upgrades cost? Does the upgrade item menu from builder work? I don't have an invoice from builder. 

3. Will Turbo tax re-calculate the capital gain tax with other income, like stock investment gain/tax, and come up with a final capital gain tax payable? 

 

Thank you!