Can I utilize deductions to make a tax-free IRA withdrawal?

I retired November of 2024 and turned 65 this year. I have no earned income in 2025.

As a single filer, I'd like to clarify some tax details with four questions below.

Consider the following deductions for the 2025 tax year:

$15,750 – standard deduction

$2,000 – additional standard deduction for being aged 65

$6,000 – additional tax deduction for eligible seniors aged 65 and older (per the OBBBA)

1) Adding up the above deductions, will this allow me to withdraw up to $23,750 tax-free from a Traditional IRA before the end of 2025?

After I take the IRA withdrawal, I plan on immediately depositing the funds into a taxable brokerage account and buying the same equities it was previously invested in; to allow the money to grow at the same rate as it did in the IRA.

Currently, single filers with a total taxable income of $48,350 or less qualify for a 0% long-term capital gains tax rate.

2) After the IRA money's been in the brokerage account for a year, for the 2026 tax year – assuming my total taxable income is less than $48,350 (or whatever the threshold will be in 2026) – will I qualify for the 0% long-term capital gains tax rate?

I'm deferring social security until age 67 in 2027. Until then my sole source of income for living expenses is currently from a 4-week T-bill ladder in a Fidelity taxable brokerage account. As the T-bills mature, every 4 weeks I transfer money from the brokerage to my bank account to pay bills.

3) If I deposit the IRA withdrawal funds in that same Fidelity account, since that IRA money will be "mixed" with the existing money in the account that I'm using for the T-bill ladder, will that complicate the capital gains calculations at all? I do have interest income from the T-bills as they mature every 4 weeks. Is the IRS able to keep my IRA money "separate" for the purpose of long-term capital gains calculations?

4) I also have a Schwab taxable brokerage account with a zero balance. Per question 3 should I deposit the IRA withdrawal funds in the Schwab account instead? Or is that not necessary; and I could just use the Fidelity account and mix those funds without any complicating factors to concern myself with?

Any help in addressing these questions would be greatly appreciated! TIA!