First thing is to gain some knowledge about handloading, as others have stated a good handload manual to get the basics, there are lots of You tube videos on the subject, be careful, some of these folks are real good at producing a video but have many have misconceptions about the subject, go with a good handload manual, Lyman ,Hornaday, Speer are good for the basics.
Tools, if it is for a rifle cartridge, a good single stage press, a balance beam or digital scale, vernier or dial calipers, Lee case length gauge/trimmer combo, cartridge base to ogive measuring tools (Hornaday offers these), powder trickler, Lee dippers (you will thank me later), inside/outside case mouth chamfer tool, nylon brush and handle, a hand held priming tool (the one from Frankfort Arsenal is good), appropriate shell holder, get two of them, bullet puller (impact style), Dies: a few ways to go here, I use a combination of the Lee ultimate die set, Forster bullet seater (the one with the dial is nice but not necessary, the regular one will get you where you need to be), Redding body die.
With the addition of knowledge the above will grow with you.