Hello Dave183,
Hope you're doing great!!
Usually you should keep your income tax returns for 3 years from the date you filed your original return or 2 years from the date you paid the tax, whichever is later, if you file a claim for credit or refund after you file your return.
You may need to retain your records for a longer period.
See this IRS article, How long should I keep records? for more details.