Hi first time applying for uc rent question pls

hi it’s our first time just had a look at some of the questions . I know we both have to make an account before merging them . Do we both have to put in the rent details or just one of us? Tenancy’s always been in my name just never got round to adding his name to it . He’s the breadwinner by the way . I’m scared u will fill it it wrong . Thank

You for your time x