Villa Marni is a beautiful place to spend a couple of days or longer in Gozo. I would suggest you go with a car, but if you don't there is a bus that passes a few steps away from the house. You can also walk to a local restaurant and Xlendi bay, but be aware of the steep road on the way back.
While in the apartment, you can spend time relaxing on the balcony with a view of the pool, or on the sofa watching Netflix, and of course lounging by the pool. By car it's 20 minutes away from the port and under 12 minutes from Victoria.