Im on Red eclipse. But you can use your group finder. Just queue for your specific role, and to the flashpoint you wanna do, and wait for a group to pop up.
Most people are friendly. But that doesnt mean you might end up with total noobs, that slow you down, or total elitists, or simply people who are used to do those flashpoints, and only want to run them trough fast.
If you are noob to group content, i recomend to go in as a DPS. As every role has typical specific things to do, acording to the fights each one has typical mehcnics. These flashpoints are usualy easy on the mechanics, so no worry.
Operations are much more complicated.
For instance Fighting the dread council the last bosses of Dread palac operation, this might look simple, but it isnt, hard as hell, all players need to know what to do at all times, the coordination between 8, or 16 people is never easy. There is alot of mechanics.
This however is my favorite final boss fight in an Operation ( this one and the Terror from behond one are great )
And this probably my favorite flashpoint final boss confrontation
Battle of Ilum/and false emperor flashpoints are part of ilums planetary story arch.
Also one thing quite important, if you are new to MMOs and this sort of group content. In looting Just need on gear that is specific to your character. for instance if you are a sentinel, only need on gear that has strengh, and medium armor etc.
Other people dont like when soemoen needs on stuff that they dont realy need.
just basic rule.
You probably can read the swtor tutorials in the codx area, to learn about game group mechanics.
i wish i could help you but i realy dont have any toon on jedi covenant. I dont know how it is the playerbase there. But on Red eclipse, people are mostly friendly, and helpfull. With a rare exception here and there. There will be no doubt people telling you to spacebar conversations, as they did it a thousand times, but given it is story mode, and your first time, if you explain it to them, people tend to be understandable, at least i never had realy much trouble with it.