I guess I'd ask a few questions first.
First and foremost....Do You have ANY access at all to lead or wheel weights, hopefully for free or very cheap?
Do You have a garage, or shed where you can smelt down scrap into alloy and/or use for the actual casting?
If you have to buy EVERYTHING from the start, Have no SAFE place to smelt and cast....as well as have no access to free or cheap lead...I'd suggest simply buying bulk cast slugs.
Before I go into a long "How to do it" or drone on about what worked for me, etc.... Go to... CastBoolits.com,
Cast Boolits Simply THE BEST bullet casting forum on the net. check out the stickies. There are several on starting out, SAFETY, what to buy, what not to, etc.
I cast 160# of pistol slugs this past winter. I am just finishing lubing/sizing them on my STAR. I've been casting since I was a kid, but times have changed, some of it for the good, but some bad. Lead used to be free or cheap. Not any more.
Many of the great mold makers are either out of business, like H&G, or the QUALITY of others have dropped terribly...like Lyman. BUT...small mold makers using CAD/CAM are building WONDERFUL molds that are affordable and available in ANY configuration you desire.
I smelt my range lead and WW's on a propane plumbers pot that holds 100 pounds + of alloy. I'm still using lead I got free or for almost nothing years back. I just started buying bar TIN to add to my alloy.
I use everything from 1# Lyman ingot molds to a custom 10# ingot mold to cast mu ingots. An ingot mold can be as simple as a cast iron MUFFIN PAN..one of my favorites...casts a round 5# ingot.
I cast with a WAAGE electric pot and hand pour with a small ROWELL ladle. I have several OLDER Lyman 4 cavity molds as well as a dozen 2-8 cavity Customs from a variety of makers. I lube and size on a STAR press.
FWIW and this will draw all sorts of ire...I'm not a fan of most LEE casting gear. It's built as cheaply as possible. I fond that there is FAR better molds, furnaces, sizers out there than LEE.
Good Luck,
FN in MT