Haven't touched mp yet, is it pretty simple to jump into, I dont want to get handed once I hop in, are the maps open like bf or is it more like cod?
Jump into Classic Warzone or 24 Player Warzone, TDM is just gonna frustrate you. Classic and 24 are a mix of game types like CTF or Domination. Some maps are large but not BF large since there's no vehicles. It's a bit more like COD. There's no aim assist so if you're coming from COD be prepared to adjust to that. All guns are unlocked at the start but they are locked to certain classes. Attachments can be unlocked by completing challenges (kill 25 enemies with this gun, headshot 5 enemies, etc).
The Assault class has good rifles, namely the Rumbler, and has a deployable shield to create cover to shoot behind from. The Support class has the most abilities to choose from and their spawn beacon and revive abilities are essential in winning the objectives. The Scout class can cloak but only use the knife while cloaked; they can also do a radar scan and highlight enemies for their team to see.
There's currently no built in voice chat yet, but it's coming soon. But party chat works, and if you join a GAF party I guarantee you will be racking up wins left and right.