Hello, I took paternity leave of 4 weeks during 2020, which was paid for by my employer. Should I check the box for Paid Family Leave?

If you received paid maternity leave (not use of sick time), it most likely was Paid Family Leave.  IT would have been reported to you on a W2 (from your employer or an insurance company) or a 1099-G.

Paid Family Leave (PFL) income is money you receive from your employer, an insurer, or the government while you are away from work for an extended period of time so you can recover from a serious health issue, take care of a seriously ill family member, or bond with your newborn or newly adopted child..  The states that offer paid leave are: California, Connecticut, the District of Columbia, Massachusetts, New Jersey, New York, Rhode Island, Oregon, and Washington.