New Player Needs Advice

Use the coop mode to farm Ai for kills. On sniper rifles it is 50 kills and 50 kills in the coop mode to unlock 2 that are very similar, then it is 200 for 3'rd and 400 for 4'th respectably.For attachments/mods it is 25,75,150 kills which can also be done in the coop mode. The other sniper that you kept on getting killed by is probably the NT-242 It is 400 kills with the specialist class to unlock. I recommend the first 2 mods for it (Dual zoom and improved cooling) 

Just play coop and lvl up all your heroes trooper classes etc etc.

Thank you both for the tips! I'll try co-op mode next 🙂

I play specialist quite a lot and run the NT-242 with improved cooling and ion shot. The ion attachment deals sightly less damage to troopers but it gives splash damage and is super effective against enemy vehicles. It’s an awesome feeling taking down opposition walkers and tanks with one little old trooper! 

Since the vets here have already pretty much covered all the general bases and given you the tips to level up (which is absolutely necessary, star cards are everything sometimes), I'll throw in another tip. It's not usually a specialists job to get a ton of kills. I've found that most of your points as a specialist comes from spotting enemy reinforcements. Initially, it was my goal to main specialists as well, but after a little time I realized I just played better as a more patient playing and long range assault trooper. 

Don't get those levels fool you, there can be good players and bad players that level only tells how long people have been playing this game, they might be good or not. You aren't doing nothing wrong this game is working like this, it is hard for beginners because it is so tedious to get better weapons.I am still quite average player even I have casually playing this game over two years now. Always be with your team members with those best players and look what they are doing and try to learn from them, never try to snipe somewhere alone if you aren't good player. You can't do literally anything against heroes or villains, just accept it. You are cannon fodder for them, game is designed like that, Stinger Pistol used to be working against heroes but then devs nerfed it also. You have to wait in lobby to get hero, there isn't any queue in this game. When you get your hero, remember that block only works from frontside and time your attack spams correctly or you will easily run out of stamina.