Basically there are two ways to approach poker:
1) The recreational way
2) The professional or semi-professional way
If you decide, that poker is your hobby, and you just want to have some fun, then the first step is to decide on a budget. PokerStars allow players to set daily, weekly and monthly deposit limits. This is a very good idea, so that you dont randomly change your mind about the budget after a losing session. And when this is done, then you simply play, what gives you the most fun. If you win some money, then thats great, because now maybe you dont need to deposit next month. But winning is not the goal or the expectation.
If you want to play in the semi-professional way, then the first step is to study and improve, for instance by taking the CC 30 day course. Then you should give yourself a reasonable starting bankroll
like 100$ and select a game format, that you want to play. This should be something, which involve playing "real poker" on all streets, but which is not to complex or time committing. So on one side you need to avoid any kind of hyper-turbos including spins, but you also need to avoid large field MTTs.
On PokerStars the best place to start is either 2NL cash tables (regular not Zoom) or the 1$ 18-45 man "on demand" SnGs. Then you grind these games, until you start winning and have build a bankroll, which is large enough to move up. Some reasonable and simple guidelines is to have at least the following number of buyins for the next limit, before you move up:
Cash games: 30 BIs
STTs: 50 BIs
MTTs: 100 BIs
The "on demand" SnGs are small MTTs, so here the 100 BI rule apply. But if you get tired of grinding only those games, you can start mixing in some 1,1$ MTTs and/or 2$ STTs, so that you get to try some different game formats. And then you just go from there. I build up a new bankroll last year starting with a 100$ deposit on PokerStars, and now after a little more than a year it sits around 3.500$.