How long have you owned this property?  Capital gains tax rates are different for short-term (one year or less) vs. long-term (greater than one year) gains.

As for making payment of your taxes due, you can go ahead and make payment now, or you can wait until fourth quarter estimated tax payments are due...January 15, 2021.

We have owned the property for 38 years.

@gettaandsteve So your capital gains would be taxed at the long-term rate.  You'd be safe to send in 20% of your profits (sale price less original investment plus improvements) by January 15, 2021.  You can make payment by check or  by using the payment options on the IRS website.  I'm linking that below.  NOTE:  I don't recommend paying by credit card because of significant "convenience fees".

Payments | Internal Revenue Service (irs.gov)

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You should make estimated tax payments for the current tax year if both of the following apply:
- 1. You expect to owe at least $1,000 in tax for the current tax year, after subtracting your withholding and credits. 
- 2. You expect your withholding and credits to be less than the smaller of: 90% of the tax to be shown on your current year’s tax return, or  100% of the tax shown on your prior year’s tax return. (Your prior year tax return must cover all 12 months.)

Otherwise you can wait to pay when you file. 

 If your goal is just to avoid the underpayment penalty, then paying 100% of the prior year tax liability is the “safe haven”

TurboTax (TT) can prepare the quarterly payment vouchers. In your 2019 software, enter at:

Federal Taxes or Personal (H&B version)

-Other Tax Situations

  -Other Tax Forms

    -Form W-4 and Estimated Taxes - Click the Start or Update button

On the next screen answer No to the W-4 question

Or you can obtain  blank IRS Form 1040-ES from the IRS. The form and instructions are at this link:  https://www.irs.gov/pub/irs-pdf/f1040es.pdf

You can also pay Federal directly here.  Be sure to select 1040ES:

https://www.irs.gov/Payments

 Depending on how much total income you have,  long term capital gain (LTCG)  are partially taxed at 0%, 15%, 20% and/or 23.8%.