A kitten can be adopted at any age. The first thing you need to do is visit your local animal shelter and see what kittens are available for adoption. You may want to ask the staff about how old these kittens are, or you could always adopt a puppy/kitten pair who will grow up together as brothers or sisters!
Adopting an older cat means that they are more mature and less likely to have behavior problems compared with younger cats. But if you’re really interested in adopting an older cat or kitten look out for special programs which allow older animals to find new homes – especially those run by rescue organisations that place mainly senior cats into loving households.