First timer, & buying 2019 High Country 381TH and now need a hitch

[KausalityKid]

I'll be picking my 2019 Montana High Country 381TH this weekend and need to buy and install hitch in my truck by then.
I have A Dodge ram 3500 heavy duty/high output dully (the one that has 30,000 pounds and has 1000 pounds of torque). It has factory installed fifth wheel ready.
Crew cab, 8" bed

Specs:
Dry Weight (lbs/kg) 13345 / 6053.3
Payload Capacity (lbs/kgs) 3655 / 1657.9
GVWR (lbs/kgs) 17000 / 7711.2
Hitch Weight (lbs/kgs) 3185 / 1444.7

Here’s what I think I know, but as always you don’t know what you don’t know.

• Some, but not all trucks, need a hitch specific to their vehicle. (True or faults)
• My 3500 needs a specific hitch rather than universal ( True or False)
• I don't need a slider(True or False) probably false
• Not sure what it means, but should get one that moves both horizontally and vertically
• Best brands?
• I need an install kit also (True or False)
• I can install it myself or should have professionals (myself or professionals)
• What should it be rated at for Maximum tow weight?

What am I forgetting?

Thanks in advance for any assistance.