How can I stop using a phone/laptop while still being able to access Gmail?

I want to stop using social media but I need access to Gmail and school websites to be able to see my homework/tasks and to communicate. I can go to libraries to use computers and that's good but not if I just want to quickly see/check any notifications or messages cuz it takes a lot of time to go there and also need to check the closing time of the library so ye...