Ghost shrimp are super easy to care for but tend to be snacks for bettas.
Out of my 17, i Have 2 that will tolerate them ^^;
Having a lot of cover will help the success rate of your shrimp.
Ghost shrimp are cleaners and have a super low bioload so you can stick them in about anything you keep clean. You will need to supplement food them, your betta wont leave any food since they tend to be pigs. I use algae wafers that I cut into smaller pieces so there wont be any extra food laying around to rot.
I think if you have live plants, you wouldnt need to add extra food for them since they will eat the algae and nibble the plants. Not 100% sure on this though, I dont have live plants.
Mostly this is from experience so if anyone is more informed on them, please correct me c: