Welcome to MWLL
Okay, the most important thing of all in my opinion:
Don't be afraid to die and don't let it discourage you.
Try to reflect on the situation and how you could have avoided getting into it, how to make the best of it or how to get out of it.
Now if I had to recommend one starter asset it would be the Rave B
because it has a mid range LBX-10 and 3xSPL for close range, and a full radar suit with gecm, c3 and bap which is a great loadout for new players.
So why is that such a good loadout for new players: The early game is very dynamic due to everybody being in light assets so staying safe at long range is difficult. The medium range LBX-10 will allow you to provide fire support while staying behind your allies and the small pulse laser provide additional damage output at close range. The GECM allows you to keep your radar on to better see enemy movements on radar without being too visible yourself since it reduces the range at which you get detected at by 500m. The C3 allows you to passively help your team by sharing your radar contacts with your allies, while giving you a small stream of passive income. Lastly BAP boosts your radar range by 200m which synergizes with the GECM and C3.
There could be so much more to write about: map awareness, positioning, movement, focusing components, twisting to spread damage, map control, back capping, ... and I don't want to write The Art of War MWLL right now, so if you have something more specific I'd be happy to help or if we see each other in game I could give more tailored feedback.
Tough I do have one beginner tactic: Pick a teammate and stick with them as best as you can, shoot what they shoot and retreat when they do. Sticking together is always helpful if you concentrate fire and share armor.
You can also join the discord if you haven't already for more active discussion, event announcements and some people using the voice channels while playing.
The wiki also provides a wealth of information.
For a web based server browser with player population stats check out spooky's stats page. It also offers extensive comparison tables for all weapons and vehicles.
I hope this helps as a start, if you have any follow-up questions or want to discuss specific topics I'd be happy to help.