At its core, Google Keep is a relatively simple web app. Especially for a low traffic scenario, literally any web framework/library and combination will be good enough. You need storage, a backend, and a front end, either all from the same package or talking to each other.
I suggest you figure out what looks interesting to learn and go with it. You can also “outsource” parts e.g. getting storage and backend as a service from something like Firebase, so you can focus only on building the front end.
I suggest you figure out what looks interesting to learn and go with it. You can also “outsource” parts e.g. getting storage and backend as a service from something like Firebase, so you can focus only on building the front end.