Family time is wonderful, isn't it?
But for those occasions when you need to get some actual work done, or you just really need a break, here are some games that kids can do on their own without any help from you. Most of us played these things during our own childhoods, but the recent trend toward scheduled or "enriching" activities might have led us to forget about them. No worries, kids still love them!
Build a fort - let them use all the blankets and pillows they can find and make a fort someplace. Anywhere you're not working is perfect! Depending on their age, this will take them longer than you think. Once it's built, have them take some games inside to play - cards, action figures, blocks, Legos - anything that would be fun to use in a fort. If you are an especially relaxed parent, you can let them eat lunch in there. If it were me, I'd let them do almost anything in there that kept them quiet.
House - so old fashioned! So fun! They get to decide who is Mom, Dad, Grandma, the baby, the dog., etc. Fun variations might be: Prairie House, Beach House, Grandma's House, Quarantine House, etc.
School - they can setup a little school and teach their dolls or stuffed animals or action figures.
Store - get out the canned goods (I know you have some!) and let them set up a store and take turns hoarding-- I mean shopping. No need for a real cash register, you can pretend with a shoe box and a calculator.
Dress Up - raid your closet and let them be superheroes, space aliens, princesses, knights, cowboys/girls - whatever they can think of. Hopefully they will act out stories these costumes inspire.
Tea Party - not just for girls! My boys used to play this for the express purpose of having horrible manners and spit-taking their "tea". Lots of hearty laughs.
This kind of imaginative play often leads them to invent their own games. There's nothing more delightful than seeing what funny things kids think up on their own. Yes, there may be a mess to clean up, but pillows all over the floor is worth an hour of happy quiet, if you ask me.