Finding this chair

Theyre good but they only recommend at 6 months i dont know about a 10 week old

No… 10 weeks old is way too young to be sitting on that chair. Their spine / bones are still soft / weak and developing.

Why do you want to sit your newborn down so early ? That bag can’t even hold their neck still yet.

If your baby can sit up with minimal falling over, than yes. I had for my twins when they were able to sit up