Cool, he will probably move towards the bottom of the tank, he seems to like to bury his foot under a rock on the floor of the tank. I would suggest (if you can) to gently try and place him on the substrate next to some rock, he will hopefully manoeuvre his foot just under the rocks and then open up, don't worry about your fish, if they are all healthy they will be fine.
Don't worry about feeding him, when the clown starts hosting in him, he will take food to the anemone whenever you feed the tank, really cool to watch.