I have a cat about 2 months old who is very aggressive he attacks my feet when I walk and any time I try to pet him he bites (hard) we got a very small kitten today who is very sweet and loving and the older cat is trying to play with it but is getting to aggressive. How can I stop this?!
This is a common behavioural problem.
Play with them as much as possible in such way that both take part but don't have to interact directly with each other, after some time the antagonism will subside and they will get along without hitch.
The issue is caused by cats being territorial: your kitten grows up, starts to become adolescent and attempts to pressure the elder into submission. In essence it always look different, but comes down to it.
P.S. If the fights are agressive, break them up by using water spray. For this purpose, use clean window cleaner spray bottle and pour full of water, they will break up and run off to lick the fur clean. Just make sure the bottle is cleaned properly so it does not contain any chemical residues.