Hey LordBlade! Welcome to the Sector!
I'm putting together a new series specifically for new players to StarSector. It focuses on the campaign and explains all the mechanics step by step, with tips dropped in to help you along.
Link to episode one! Working on additional episodes nowTo answer your specific questions:
1. It's good to have at least one tanker in the fleet, as well as some ships that can hold cargo. That will allow you to take exploration missions if you desire. Besides that, salvage what combat ships you can find. I'd recommend looking for midline ships as those can mount early game weapons while still have shields to remain survivable. I'd recommend saving your money for supplies and fuel early game, so try not to buy many ships. It can get expensive.
2. [REDACTED] fleets are spooky AI ships. Avoid them in the early game. And as part of that, heed the warnings of the warning beacons. If the beacon is red, DO NOT enter the system! It's probably better to abandon whatever mission was there.
3. There are missions that will pop up in your feed, like bounties, or exploration missions. Those can pay a lot but you'll need a fleet setup for them. Otherwise there are missions you can get from the bar, those usually explain themselves pretty well. Most bounties you'll get paid for as soon as you kill the bounty ship in question. Otherwise, if you like a particular faction, you can apply for a commission, which pays you monthly and gives you access to that factions ships / weapons. However, you then represent that factions and automatically are at war with it's enemies. A Hegemony commission is great for a first timer.
Otherwise you can develop contacts which will give you lots of missions. Usually you get an opportunity for a contact after a bar mission.
Hope that all helps!