Hi
@sharon w, You’ll LOVE Semana Santa (be prepared for crowds like you’ve never seen in your life - hard to escape but oodles of fun). Find an English-speaking local to explain what/how the processions are and which ones to see. You can spend days (and nights) enjoying the spectacle.
As for accommodation, you would be best to stay in the centre but places around the Cathedral will be noisy almost 24 hours a day. Stay in the ‘old town’ but try for a place (say) nearer Plaza del Duque (where the big El Corte Ingles is). This is a wonderful spot to see all the Pasos (processions) as they head to the Cathedral. I used to live near here and it’s a gorgeous area and very central. There are quite a few AirBnB places in this area too. Worth signing up if you’re not already a member.
Another suggestion is to stay in Sevilla and enjoy the atmosphere 2-3 days after Semana Santa - you’re sure to miss the bubble then.
If you would like to ask specific questions, please PM me.
Buen Camino, Grace