Help! Need infomation regarding mods/game mechanics

Hi, im about to try and learn lua and i have this idea for a simple gamemode
which id like to make. Its a take and hold territory type mode, im wondering if its
possible to script entitys/areas that can be controlled. Also id like to know if there is any
rpg type skill tracking systems out there, like measures weapon skills etc and in turn
makes your character level and get better over time.

Also any can resources be edited like if i downloaded a Swep pak could i remove certain weps?

Thanks

yes u can, ?