i don’t have a cellular icon on my iwatch 6

Again, is your Apple Watch a cellular model? Yes or no? Does it have the red ring or dot?

If not doesn't, then it's not a cellular watch, and it cannot be setup as such.

Does your watch have a red dot or a red ring around the digital crown button face?

If it does not, it is not a cellular watch and so has no option for cellular service so no icon.

Are you having trouble understanding what you are being told? Look at the picture posted. Look at where the arrow is pointing. That’s where to look for the red ring, on the digital crown, NOT on the screen.

Look at the big round button on the side of the watch. The one the arrow is pointing to in the picture I posted. The ring you are looking for is not on the screen.

Are you saying you cannot see the picture I posted?

Have you setup a cellular plan?;

Set up cellular on Apple Watch – Apple Support