First, you can log on to your account with the social security administration and check that they have your earnings history correct.
Then, the general rule is that you can discard most tax paperwork either 3 years or 6 years after the that you filed or after the filing deadline, whichever is later -- so for 2023 (which was due April 14, 2024), you could throw away your papers after April 15, 2027 or 2030. (Normally, the IRS can only audit you for 3 years, but they can audit you for 6 years if they allege deliberate fraud or an understatement of tax by more than 25%.)
You should keep paperwork related to property for as long as you own the property plus 3 or 6 years after you sell, since invoices for improvements, closing costs, and so on, can affect the tax you pay when you sell.
You should keep information about the cost of investments for as long as you hold them, plus 3 or 6 years after you sell, for the same reason. However, if you buy investments through a broker, they are probably keeping those records for you.
If you make non-deductible contributions to a traditional IRA, you should keep copies of your form 8606 that you file with your tax return as long as you live, or at least until you withdraw all funds from your IRA.
