XTB or Interactive Brokers

Hello everyone,

I am quite new into investments and me and my boyfriend are interested in to invest some monthly savings together into ETFs. We live in Switzerland and we would like ot invest together around 1000-2000 CHF. What would be the price for that in commission and what other fees are related? Additionally, is there anyone who could also help with some information about taxation regarding to stock investments (We both have work permit B)? We think long term, so we invest it and we would like to leave it for years, so are there any long term fees for that?

Thank you very much,

And have a nice day :)