Can anyone explain why qui is protecting Jian yi,doesn't he work for tian's brother?

Yes and He Tian's brother is also working under someone else, which is probably the person who wants to project Jian Yi

something to do with his sketchy dad who had some business with them, when he died his mum was the one who took over his work and stuff. So it's bc of his mum and her connections... I think..

What? Where was it mentioned his mom took over his work??

It was never mentioned that she took over, I suppose it's more of a guess. Personally I don't think she took over but Jian Yis grandfather was in the mafia and he's is still alive. There's a chapter where he told his people to protect Jian Yi. I don't remember which chapter it was but he said something like "I still have many enemies, so protect my grandson"

Yes this is exactly what I understood from that chapter and what I thought everyone collectively understood, so I was so confused when someone said her mum took over so I wanted to make sure if I missed something cuz ??? what