How do I transfer my apps from my PC to my iMac

Just upgraded from a Windows PC to an iMac, turned on home sharing to transfer my itunes library across but it's not picking up apps, podcasts or music.

I checked apple support but you need an IT degree to work out what the **** they're talking about, Home Sharing doesn't work, I have no idea how to network my computers.

Simple language on how to transfer across, I thought it would all be in icloud, but apparently not - very annoying