How to distinguish a normal bookmaker with an honest bonus system from one that simply lures "up to $100 for the first deposit" and then does not allow you to withdraw the money? Maybe someone can tell me which features should be checked immediately before registration?

What helped me was that I simply began to carefully study the rules before making a deposit. But not all bookmakers are responsible in explaining all the nuances to beginners. For example, at https://om.1xbet.com/en it is convenient that there is a separate page with a full description, and you can immediately see: where you can place a bonus, what bets it applies to, what to do with it later. No surprises, as is the case with others.