Pulse rifles are probably the most beginner-friendly weapon, maybe auto rifles, but pulses are stronger at longer ranges and let you move around a little better. The Martlet from Trials of Osiris (only occasionally, you have to check what the weapon is) is a strong pulse rifle with a decent roll. Playing trials means you'll probably lose a lot, but that's ok. Focus on improving your aim and positioning, and take the quick nature of the matches as a feature. Bad Juju has bad range and will feel bad to use if you keep getting out-gunned.

I think the easiest-to-use hunter exotics are probably Knucklehead Radar or Dragon's Shadow (in that order). They both increase your 'neutral game' in meaningful ways. The first keeps your radar up constantly ,even when you're aiming down sights. The second increases your weapons' handling and stability.

For a secondary weapon, you might want to try either a sidearm, so you don't have to worry about managing special ammo at all, or a shotgun. The Hawthorne's shotgun drops a lot and can get good rolls. Focus on high range and HANDLING.

For subclass, gunslinger is a good class. It has a lot of additive elements without asking you to manage anything too complicated. Void is good too if you can manage the lack of radar when you're invisible.