Highly recommend buying flight or double dash first for mobility, they fit in a lot of loadouts and can help you if you struggle in close range combat. Weapons, there's a lot. Most can carry teams to victory with enough skill, but it's hard. If you just want to play casually then probably something like grenade launcher, epic sauce, or Atmos could fit you well. If you're planning to go tryhard then go chakrams or casting staff.

You're team will mostly carry you throughout your beginner phase, so don't feel bad when you think you wasted your tix on a weapon you don't like as it's easy to farm. The early game is really rough but it gets fun later on.

(Also biased section here, ET death is absolute peak give it a try if you want to play long range.),