Hi,
Everybody who designs a pcb has the same problem, therefore you may find the answer thousands of times in the internet.
Also it should be in the documentation of each pcb layout software and at each pcb manufacturer.
Many pcb manufacturers can simply use your pcb board project file...But gerber has it's benefits..
Best is, to talk to the pcb manufacturer.
*****
You don't say what board specifications you have...
For a standard 2 layer from top to bottom:
* milling pcb outline (gerber)
* top silk screen
* top solder stop
* top copper
* bottom copper
* bottom solder stop
* bottom silk screen
Additionally: (non gerber)
* drill configuration
* drill data plated
* drill data non plated
And informations like: (non gerber)
* total pcb thickness
* copper thicknes
* color...
* edge connector gold plating
* finish
* panel setup
* approval informations
* buried via or blind via informations
If the pcb manufacturer produces the SMD stencils: (gerber)
* top stencil data
* bottom stencil data
(If the stencil is made by another manufacturer, but the pcb manufacturer sets up a panel for you, then you could ask the pcb manufacturer to "multiply" the stencil gerber data according panel setup. Otherwise you need the precise panel setup.)
I hope I didn't forget anything, I don't have my checklist by hand.
Please write your own checklist.
Klaus