Welcome to Reef2Reef! Agree with the research before putting anything into your tank. Time and patience rewards all reefers, the minute you rush is minute things go wrong. As
@T-J mentioned watch your water quality (parameters and such)
For your Kenya Tree, they are a hearty coral... you can try a couple of things.
Glue back to it's rock
You can try the rubber band method and have it self reattach
or you leave it on the rock in a low flow area and see if it reattaches itself.
Food for corals, I'd look at ReefRoids, Benepetsm Red Sea Coral Energy Plus... I use all three just make sure you follow the instructions. Overfeeding can cause spikes in nitrates leading to other big problems.
This forum is a great place for answers all you have to do is ask. Make sure to include pics and as much description as possible. Looking forward to hearing from ya!