In general you don't eat it as a fruit. Either you make liquer or marmelade or this 
I can find receipes if you want, but in greek...
Discussion
I've been told you can eat it, with a skin too.👀
I mean, technically you can... 😅
You can. Not recommended though 😀
I have a dwarf kumquat, ate the fruit just yesterday, its good, but you need the right variety.
I got very excited when I saw a friend's huge one laden with fruit, but they were terrible.
Wish I'd kept the tag that came with mine, I can't remember the variety name... :(