Taxis and uber/lyft, like Camden said. I have heard Las Vegas' public transit is not great.
I kind of am not a fan of casinos because I find them overwhelming, but! Some of the casinos have some cool stuff, one of them has an aquarium for example. So maybe if you're doing lots of loud/overwhelming stuff make sure to break it up with some calmer stuff.
One thing to note is both Las Vegas and southern California are going to be warm even in February (Las Vegas averages around 19c in Feb, for example), so make sure to layer clothes as it's not as cold as one might expect for the end of winter.
Like Camden said above, I'd try to maybe recreate some things, bring a comfort object, and make time to spend by yourself!