Answering your question in order, shoot letters in order followed by numbers in order. Always shoot when you can, but never tag J!
Use heavies whenever possible, lights for when FC asks for them.
I would use tracking whenever possible, assuming you have meta guns with faction ammo, sometimes you may wanna load an optimal, such as in NRF last waves or in Assault sites, but you should have plenty of falloff to cover you.
In TPPH and NRF you always wanna drop drones when the fleet is first coming into site and assign them. If you are late on grid, get to your anchor first, then drop drones, as they are slower than you are so it saves time to carry them there. In TCRCs only drop drones when called for as they can cause some split aggro.
Sites will come more naturally the more you fly them, as there are only 3 HQ sites we run normally, it'll come quickly
A quick run down of each site TPPH or True Power Provisional Headquarters, 3 rooms, last room has 3 waves followed by a tower bash, the slowest site
NRF or Nation Rebirth Facility, 1 room, 4 waves, no tower bash
TCRC or True Creation Rebirth Facility, 1 room, respawning rats with a tower bash, the fastest but most dangerous site, make sure to listen to your FC in these sites!
Feel free to ask questions, and if you have trouble understanding ask if FC could type it out in fleet chat for you. Welcome to WTM o7