If you cash in a life insurance policy for the cash value, a portion may be taxable.
Per IRS Publication 525 Taxable and Nontaxable Income, page 21:
Surrender of policy for cash. If you surrender a life insurance policy for cash, you must include in income any proceeds that are more than the cost of the life insurance policy. In most cases, your cost (or investment in the contract) is the total of premiums that you paid for the life insurance policy, less any refunded premiums, rebates, dividends, or unrepaid loans that were not included in your income.
You should receive a Form 1099-R showing the total proceeds and the taxable part. Report these amounts on lines 4c and 4d of Form 1040 or 1040-SR.