ICJ orders Israel to prevent genocide in Gaza, stops short of ordering ceasefire

What's the ICJ's actual ability to enforce this? "Orders" sounds like they have some sort of weight to throw around if Israel doesn't comply, but I'm not familiar with the ICJ or what possible consequences could arise if Israel simply decided it was going to do what it wanted.

In theory i think they are supposed to ask the security council to step in if the order is ignored. Which would be unlikely to do anything, so nothing.

I think its likely israel will comply. The order is pretty weak and mostly stuff israel already claims to be doing. It wouldn't be worth the PR hassle to ignore it.