Machika Enameled Steel Paella Pan 18 inch (46 cm)

If I have pan that’s serve 10 can IAlso use for less servings?

Want to use on weber charcoal grill. when measuring 15 inch pan how much do handles add to diameter?

What is the height of the 20 inch pan ? Thanks.

I know this is not flat - is there an accessory I can get to use this on a flat electric stovetop?