Thanks your all your comments.

I really don't expect to be successful or anything, just to have fun and be able to share my passion through playing with others is fine. I guess my problem is that I only have a digital piano that is like unmovable (heavy) and an acoustic guitar( which i fingerpick/strum chords on, can't do much complex stuff) so I can't really contribute much if i'm in a band and need to bring an instrument to practice. I'm thinking of getting some sort of synth - arranger, workstation...but i don't really know the difference. What should i get if i want a lot of preset sounds that can be changed, create new sounds and can make my customized drum loops and fills/change between loops easily? What i want is a synth that can be played with a band as background (eg. using synth pads) harmony and also provide drum beats (and maybe even playing bass guitar parts in left hand).

Also, does it take long to learn the basic functions of a synth (like creating drum loops, tweaking sound effects)? I can pretty much self discover the functions of the synththrough trial and error right? My digital piano has some basic functions like layering, bending, modulation, reverb, and preset drum loops with intro,ending,fill-ins. I would expect a synth to have way more functions than that, but i don't know how much learning will be required.

Thanks