It sounds like you are trying to enter either your mortgage interest 1098, a 1098-T or a 1098-E. Instructions for several options are below:
Please see this FAQ to enter your 1098 mortgage interest: https://ttlc.intuit.com/replies/4793767
Please see this FAQ for instructions on how to enter your 1098-E: https://ttlc.intuit.com/replies/4801974
Please see this FAQ with instructions to enter your 1098-T: https://ttlc.intuit.com/replies/4194409