I want to create an additional email address for myself

Hi ev1, firstly, I'm really ignorant about technology in general so please.. for any responses, please speak in simple terms 🙏🏽

(If I had a grandkid handy, this'd be solved in a snap, right? LOL)

I'd like to create an additional email address that I can use when registering for apps and such so that my primary email inbox doesn't get clogged with the spam that results from my email address being sold for advertising purposes.. is there a way to do this through the Xfinity app? Or how else can it be done?

 I don't have a desktop or laptop anymore, I'd have to go to the library to use theirs..

Thanks for any input!

(This question IS posted in the forum from another user but it's years old and the link provided to that answer doesn't work anymore..)