Professions help

After coming back to maple when I'm bored, I've been putting off this whole professions thing. It's really confusing to me and I've tried to google and even search SP for help. I'm still super confused about how to do this and how it even works. Does anyone have a simple, and I mean super simple, guide that you can share?

I'm a blaze wizard and I chose Alchemy and herbalism. Not even sure if that's a good idea lol....