C++ database android App

[Jarias]

So im trying to create a database app for a company where they can store all their clients information. Im just starting out with coding but i decided this was a good challenge to try to figure out. The problem Im having is Im still just learning c++ as i go and I know that things get complicated with writing an app w c++. I know im going to need an sdk and ndk which i have downloaded. However what im here to ask about is if anyone has done something like this and can at the very least let me know what else what else I need to learn to make this or if they can help me with any other part. I was in the process of writing like a class or struct to hold the different variables of clients such as phone numbers and addresses but i was having difficulty pulling them out of the file, and when trying to find help online, people keep mentioning sql or something to connect the c++ code too. I apologize if I am all over the place, its my first time actually asking something in a forum like this. Thank you for your time.

And yea I know theres plenty of apps already out there to do something like this but i wanted to try it out as challenging myself is how i like to learn.