The T4A box numbers do not match the Income Tax form numbers for CPP income benefit

Taxable CPP benefits are in Box 20 of the T4A form but the tax return asks for box 16

Seniors and students

If you received Canada Pension Plan Benefits, then you would have gotten a T4A(P), not a T4A. You can select TurboTax 2024 from the top left, and then search for T4A(P).