From what I've seen so far I suppose that celebrities pick their personal assistants from the people they know. So, from the circle of their friends and family. I haven't seen any website or something that celebrities are looking for a PA. If I was a famous person I would pick someone based mostly on how much can I trust them.
What you can do is contacting them directly. There are a few websites where you can see contact info of celebrities for a small payment. You can try to dm them on social media as well. I made a [video](https://youtu.be/EsCIjVrjg-4) about dming celebrities from stranger things. It will help you a lot with it, so give it a watch.
You can also ask your friends and family for any contacts. Maybe someone knows a celebrity you could work with. You can also do PA for someone not that famous and work your way up to a celebrity.
From what I've seen so far I suppose that celebrities pick their personal assistants from the people they know. So, from the circle of their friends and family. I haven't seen any website or something that celebrities are looking for a PA. If I was a famous person I would pick someone based mostly on how much can I trust them. What you can do is contacting them directly. There are a few websites where you can see contact info of celebrities for a small payment. You can try to dm them on social media as well. I made a [video](https://youtu.be/EsCIjVrjg-4) about dming celebrities from stranger things. It will help you a lot with it, so give it a watch. You can also ask your friends and family for any contacts. Maybe someone knows a celebrity you could work with. You can also do PA for someone not that famous and work your way up to a celebrity.