you need to know what size house breaker, length and gauge of wire from
the house, and subpanel main breaker are involved first, less the well
pump power in use, to see what's available for use at the well house.
then you'll want to trench and bury perhaps in pvc or conduit the
proper gauge wire to your locally required depth for a least two
circuits and want additional shielded cable for the camera and some
conductors for doorbell/telephone/gate sensor and control circuits. you
may even want to trench below the frostline and send some water there
or sprinkler system lines for the future. this is a good time to check
for your underground buried cables with a local hotline and make sure
your gate is inside the property line on your survey. whether you'll
need yellow buglites or maybe use a low voltage, decorative, LED
lighting system will be options. maybe pick out an attractive
distinctive fixture with an address plate and name.
this project will be more attractive then the cheap dim solar units
with the now dead batteries from 3 years ago.