1. An old Nike ball as in the replicas I presume. No, you've just started out, the ball barely matter. Unless you're rich, don't buy it until you know you want to freestyle for a few years. The shoes on the other hand matter a bit more. If they're indoors you're good to go, it doesn't have to be fancy but you can't really freestyle with running shoes.
2. In terms of lowers? If you're training you should first get your atw, htw, hatw records up and learn to do a few cross overs. These will teach you the correct motion for other moves and your stamina will build up. It's important to make your atw, htw, hatw and co clean so when you develop, your freestyle won't look like shit.