The kittens in my experience require more eyes and care. I wouldn't leave them alone for so long, but again just my experiences.
For the first timer items, just ensure the best QoL for the gato. I recommend:
- Getting them their own space, so a cat tree or a hut/sleeping pocket. This will become more apparent when they get older.
- A whisker friendly food bowl, preferably elevated.
- A large enough litter bin, preferably with a low lip for entry. Get a large ass mat for under the bin to catch litter if they're jumpers. Again, the size is for allowing them to age into stuff properly.
- GOOD wet food. The mainstream stuff is fairly ass. You have to pay more for better food but you can avoid making certain feline diseases worse in the long run if they ever trigger. Dry food is alright but its dry and lacks moisture. Wet food is better for health.
- A safe area for window viewing for mental stimulation. Cat TV on YouTube can help offset this, but nothing beats the real view and sounds.
Do NOT declaw them. Treat them with attention but also make sure you let them be when they want. Some people say to give them their own room or w/e to start with but any cats in my care always had the full living space available on Day 1, but this was with more grown cats. Some people don't like it (???) but I love having the cats around anywhere.
Depending on your location, you can get cat services and good food samplers at certain shelters.
Brushing is cat dependent, but you can work your way into brushing them over time with treats.
I know you're probably leaning kitten, but an older cat needs just as much love, if not more. Think about it.
Please be a good cat ambassador and I hope it all goes well. May your bond be forever and unbreakable, word to Shannon Sharpe.