New owner help

Alright, so I was with a girl who brought 2 cats and adopted a third as a kitten along the way.
6 years and she abandoned all of us in a fit of midlife crisis and menopause.

She was going to take 2 of them but is now back to adopting them out.

I’ve never been a cat guy and she did the primary care for the entirety of the relationship (I looked after the dogs)

I live these lil bastards and don’t have the heart to let them go. It was one thing if she took them and I could still see them occasionally as her and I have remained civil and will eventually be friends.

1. I hate litter, how do I make this easier. Is there a better type, automated solutions?

2. The Furr, how the hell do you stay on top of that?

3. Ruining all my furniture. We had bought a new couch a year or two ago and it’s toast. Between the puppy and the cats it’s time for a new one. How do I keep them from ruining it? I’m thinking leather as it’s am easier to clean esp. with regards to Furr.

4. Any general advice on how to keep them entertained especially at night when they stalk me in my sleep and wake me up.

Thanks!!