hi can anyone help me?

My son and his girl brought me home an hawiain(might be mispelt) umbella tree from work,they was going to throw it out,so the kids rescued it.It is huge and over rooted and now some of the leaves are turning brown and falling off in different locations.I checked the soil wetness every few days when they first brought it home,it seemed to need water fast so I put it in the shower till the water was coming out of the bottom.It diffenitly needs to be repotted.I have a few Questions:1 Do these trees need to be pruned,if so how? 2 Can it be broken up into different plants,if so how is it done?3 How big can they get?4 How often do they need food? THANK YOU FOR ANY HELP
