Look at my flame tip nem when I first received it. Drip acclimation, into my tank and it was looking beautiful for months....until I killed it by dosing.
Anyways so you have an anemone now! And its not looking good
Two things I see wrong with it in your picture.
1) shrunk and guts coming out
2) its slightly bleached. Bubble tips are not suppose to be white/pink. You will see pink BTAs but those are rare. Most white/pink bubble tips look that way because theyve lost a good amount of their zooxanthelle, the stuff that allows them to photosynthesize.
What to do? Move him to an area in your tank that does not get too much flow or too much light. Help him attach to the rock. He will move when its ready.
Some people do recommend feeding, i do recommend feeding it a little mysis. Dont stuff him with big anchovies, he'll probably throw it up or let it go.