Social Security’s main function is to keep seniors, the disabled and widows out of poverty. It’s meant to be a piece of your income during those periods, but shouldn’t be a significant percentage.
The easiest way to think of Social Security is they are just an insurance company, like your car insurance. The way you pay your premiums is through your tax contributions from your work. If you are a W-2 employee you pay half the tax burden, and your employer pays the other half. If you are self-employed or a 1099 worker the total tax burden is on the worker to pay.
When you file your taxes with the IRS, they will eventually send your wage information to the Social Security. It’s for this reason that, depending on when you were born, Social Security would send you an earnings statement. The purpose of the statement is your you to verify the wages were recorded correctly so that if/when the time came to utilize Social Security you know you are being paid correctly