Building an app implementing a database

Hi everyone, i'm currently trying to create an app implementing a databse. Let me explain. I have different session file in my documents, each session having players, each player having different caracteristics. I created the classes session, players etc with object oriented pogramming in Matlab. The problem now is the creation of the interface. What I would like is :

we have a list of different sessions at the beginning, session that are created based on my files.

When selecting one or several session, it opens a new list displaying the players who participated in this/these session(s).

We can then choose the player(s) and different caracteristics appear. Again we can select different caracteristics.

I've looked online, the documentation, different forum and stuff like that, i've tried different things but nothing seems to be working. I really need help, if you know how to make the first step it should be then similar for the next ones.

Thanks in advance for your help.