Badlion Client has an integrated timer can i use it? Btw im on 1.16.2 Minecraft java

Ask in the Minecraft forum.

I mean if the Timer works correctly I would say there's no problem with that. xd

Directly from the Minecraft game rules: [quote]Badlion client is considered a mod and is banned[/quote]

In general if you're not sure whether something is allowed or not you should check the game's rules. If the rules aren't clear, then you should either make a post in that game's forum, or if there's a Discord server for the game you can ask about it there as well.