people run all multi-cannons, or all lasers all the time, it comes down to experience and preferences
some people just hate ammunition and want to be out for hours... they go with energy weapons
all plasma accelerators
all railguns
all pulse lasers
all multi-cannons
these are all common, but I guess people mix-n-match more often.
multi-cannons + pulse lasers is imo cookie cutter for starting out. Tutorial has the 'right' setup for the first 200 hours of gameplay imho.
you will no doubt be filled with confusion for the next few weeks, I highly suggest you watch some Elite streamers and youtube videos to become more familiar with gameplay