If I get a BARITONE GUITAR CAN I ?

Well it's a baritone so you're always going to be playing in lower tunings (B-standard and lower), and you're always going to have heavier gauges on it, that's the whole point of a baritone. I have an Ernie Ball Baritone and I generally keep a custom set of 12 16 24 32 44 62 on it. The tunings I use are generally drop-A#, drop-A, G#-standard, and drop-F#. So you shouldn't have to restring it (unless you have REALLY heavy strings like 80 gauge) but just keep in mind that it's made for those low-tune setups. Don't dream of playing songs in E-standard.