My personal opinion: fake coral glued to wood is not going to look very good... you are mixing two things that do not occur together, FW
and reef. That being said, you can use super glue or glue sticks, so long as the glue is dry before you submerge it.
I'd suggest going with either nice fake plants or even better, live plants. Resist the urge to put in fake coral. If you stick with the hobby eventually you aren't going to like it. Save the coral for when you get addicted to aquariums, and build a reef tank!