0. Any uninvested dividends in your brokerage - you probably have this brokerage selected to reinvest dividends, but you can change it for future needs. You already pay taxes on these dividends, so it's not bad to leave them uninvested so you can send them to an IRA or use for other expenses.
1. Roth IRA contributions (no tax or penalty) - limited to however much you've put into your Roth IRA over the years.
2. Roth IRA earnings withdrawal for first time homebuyer (no tax or penalty) - limited to 10K, and you must qualify as a first time homebuyer.
3. VTSAX in brokerage - you pay tax on the difference between what you paid and what you sell it for, based on the oldest purchases. If you're showing a gain of 50%, you'll only pay taxes on 1/3 or what you withdrawal:
$150 sold, $100 paid = $50 gain
It's probably to your benefit to sell VTSAX in your brokerage account to fund your traditional IRA because tax on your brokerage account is limited to your gains only, and tax tables for capital gains are lower than for income.* But there are exceptions, and you'll have to do the math if you're using your 2020 traditional IRA contribution to lower your income to qualify for things like the EITC, or child tax credit, or ACA health care benefits.