Re: English in Bellinzona
Hi there and welcome.
There's an expat group in Lugano that is quite active on FB. You may want to check that out as a way to reach out to other English speaking families. It's called "Expats in Lugano Switzerland".
There are 2 English language schools here in Ticino, Tasis and International School of Ticino. Both are suitable for children of your child's age but I am not aware of any after school activity that is just in English or for English speakers to be honest, other than those arranged at school which specifically target the students' community and I do not think they are open to anyone.
I know at Tasis the school library is open once a week to everyone and this may be a way to get to know other English Speaking children but ways of making contacts might be rather limited.
Please feel free to ask for more info.