Trying to create a password protected db accessible through command line (Terminal/Linux) on any computer, where to start?

I'm pretty new to coding so I apologize for the somewhat noob-ish question. Essentially I am trying to build a database that I can access through terminal, in a similar way to a website that is accessed through the internet. It doesn't need to be fancy, or really that secure, but I'm looking for a way to store data/notes in a barebones way that I can access anywhere with internet and not using a browser.

I have a pretty good Raspberry Pi (8gb of ram) that I can use to help host things, as well as collect data. (I'm thinking of attaching a temperature sensor to it that collects data and puts it into the database).

I'm also open to plugging in the database to a website. I have some basic HTML and hosting experience, but nothing too crazy. I don't really need to do this, but I think it might be fun to do too.

I'm open to using something like Netlify or Digital Ocean, but frankly I'm not too sure what their role would be...

I assume the database would be MySQL, so I am in the process of learning that.

Frankly, I'm just at a total loss on where to begin. I suppose I'd start by building a local database on my Raspberry Pi, then figuring out how to connect that to the internet, maybe having a cloud backup too to access data in case to Raspberry Pi goes offline.

I think it would also be cool to require a password to access through terminal. I want to try and do it without having to install anything like wget through terminal too, (as I think you need admin perms to install stuff like that and I want to be able to access the data through any computer)

I'd also love to be able to edit the data, but that might be a bit more advanced.

Basically just looking for ideas on where to start! I think it's a pretty cool project that I hope I'm not completely underestimating.

TLDR: Trying to learn some basic coding skills through a database and network project, looking for ideas on where to start.