I forgot to enter the receipt for a large purchase. How/where do I amend this?

[xmasbaby0]

You do not enter "receipts."    Are you asking about entering  an amount for state sales tax?  Did you e-file already?   Did you use your standard deduction or did you enter enough itemized deductions to exceed your standard deduction?   What large purchase are you referring to?   Did you also enter any other state tax like property tax when you prepared your return?   What is on line 12 of your Form 1040?

[Retta1946]

I purchased a car last year and forgot to enter it. Now I cannot find where to enter a large purchase

[xmasbaby0]

@Retta1946 If you have not e-filed yet

SALES TAX

You can enter the sales tax you paid for the car you purchased in 2021 by going to Federal>Deductions and Credits>Estimates and Other Taxes Paid> Sales Tax.  You will be asked if you paid sales tax on a major purchase, and you will be able to enter the sales tax you paid for your new vehicle. 

Sales tax is an itemized deduction. “Major purchases” that you can enter for the sales tax deduction include:

Motor Vehicles (cars, trucks, motor homes, RV’s, sport utility vehicles and off-road vehicles

Aircraft or boats

Mobile homes

Manufactured housing

Building materials for major home improvements

You cannot deduct: furniture, jewelry, home electronics such as TV’s or computers

https://ttlc.intuit.com/questions/1901222-which-deduction-should-i-choose-sales-tax-or-income-tax

https://ttlc.intuit.com/questions/2566624-how-much-sales-tax-did-i-pay-last-year

https://ttlc.intuit.com/questions/3148443-how-do-you-define-major-purchase-or-major-item-for-the-sal...

https://ttlc.intuit.com/questions/1900791-how-do-i-find-my-local-sales-tax

https://ttlc.intuit.com/questions/2566624-how-much-sales-tax-did-i-pay-last-year