[AndySedeyn]

You should first know how the rest of the player's data is saved in the gamemode. Is it making use of a relational database such as MySQL, SQLite or is it using a file processing library such as Y_ini, Dini..? Once you've concluded that, you should learn how these libraries work. You can then edit your gamemode so that it saves the player's data.

Tutorial MySQL: https://sampforum.blast.hk/showthread.php?tid=574714
Tutorial SQLite: https://sampforum.blast.hk/showthread.php?tid=262417
Tutorial Y_INI: https://sampforum.blast.hk/showthread.php?tid=570912
Tutorial DINI/DUDB (Deprecated, I don't recommend using this): https://sampforum.blast.hk/showthread.php?tid=270787