How do I pay my taxes in full?

This depends on what form you are using, such as 1040, 1020, 941, and so forth.  But if you are like most people and you are talking about personal income taxes from your 1040, you can mail a check, pay by phone, or even pay using an app.

See page 58 of these instructions 

https://www.irs.gov/pub/irs-pdf/i1040gi.pdf

  If you have federal tax due you can pay by mailing your payment with the 1040V voucher, having the payment taken out of a designated bank account, or you can pay directly on the IRS website.

https://www.irs.gov/payments/direct-pay

You must pay your state tax due using the state’s preferred method of receiving payment.  For most states that will be by making a payment to the state’s own tax website, or by mailing a check or money order.

https://ttlc.intuit.com/questions/1900884-what-are-my-options-for-getting-my-state-refund-or-for-paying-any-state-taxes-i-owe