What Camera filter should i use for a nikon dslr?

I have a nikon d500 dslr and i just wanna know if i can use any filter to it or is there a specific size for it, if so what size is it?

Most of us regulars here use and recommend UV filters. They do very little to effect your photos but a UV will protect your front element from those now and then mishaps.

Check the front of your lens. You'll see numbers around the rim. One of those sets of numbers will
read 58mm or 72mm, what ever your lens size. That's the size you need… What ever it reads.

I think you mean D5000, in which case it matters what lens you are using. The lens that comes with the camera- the 18-55 should be a 52mm thread. It should say on the lens itself, but it will say in the lens description

Each lens you use will most likely need a different size filter. UV filters (good quality ones) are handy to keep on the lens to help prevent scratches.dirt on the front lens element. Don't buy cheap filters as they will often have a nasty colour cast.

The filter diameter you need will usually be marked in mm on the front of the lens (near the screw thread). If it's not, any online photostore will give the filter thread size if you do a search for your particular lens.

If you are using the kit (18-55mm) lens on your D5000, it has a 52mm thread.

I think you should go with Hoya 58mm Circular Polarizing Filter

Reduces the reflection over non-metallic surfaces
Increases color saturation
Better contrast
This does NOT affect the overall colour balance of a shot

Each lens should have a symbol similar this ⌀ or a rotated capital Phi. With it should be a measurement in mm. For an Nikkor 18-55mm lens this is 52mm. That means any 52mm diameter filter will fit directly onto the lens.

You can also use any filter with diameter greater than that of the lens, however you will need a stepping ring to use the lens with the filter. For example if you wanted to use a 77mm filter on your 18-55mm lens, you'll need a 77mm-52mm stepping ring.

Further more different filters do different jobs. Generally outdoors you should consider using a UV filter. For saturating the sky, controlling reflections something like a CPL is more useful. And indoors you could use no filter at all.