I had two kittens, siblings, and whilst they did keep each other occupied for hours at a time, they also liked time alone, with us. Not just cuddles either, they enjoyed active playtime.
Toy recommendations...our two loved things attached to strings for them to chase, a pingpong ball (thry that with them in a dry bath....hilarious), a cardboard box with holes in it and interesting things inside for them to "find", and a champagne cork that they could ping about themselves. There's loads of expensive stuff you can buy them, but ours preferred the simple stuff. A cat nip mouse never went amiss, either.
Kittens are utter vandals when they're tiny - one even perfected the art of climbing wallpaper, so be prepared for scratches and damage to fabrics and precious things. Don't wear your best cashmere jumpers.
Once they're spayed and allowed outside, they calm down inside, as they come in mainly to relax, sleep and eat. The carnage happens outside. Have a "live trap" or two in the house as they're going to bring in live rodents at some point. They all do....
Have them microchipped as soon as you get them. If you plan on using a catflap, you can get ones now that are programmable to only work with your cats chips, meaning no uninvited visitors.