You’d probably want to start off with a ranged character, and definitely one with a natural wind walk/escape. Clinkz is usually the best beginner char.
For builds, every character usually has one solid build you can always rely on, but you need to be able to adapt… that usually comes later. Usually your items match your char type. So get items that give a lot of intelligence to int chars, agi items to agi chars, etc. There are a bunch of exceptions, but you don’t need to worry about that now.
If you’re an intelligence character, you’re almost always working towards either a guinsoo, scepter, or skadi.
Agility usually likes butterfly and crits, and if you need the movespeed, sange and yasha.
Strength is usually a heart of tarrasqe.
The main thing you need to remember is that ORB EFFECTS DO NOT STACK. This is probably the most confusing part of the items. Some items are orbs, some aren’t. Some orbs are buffs, some orbs are debuffs. Debuffs will stack with buffs, but not with other debuffs. Some orbs are procs, and will usually stack with other orbs. So for example, you can get life steal and skadi, but not skadi and diffusal. This is probably too advanced anyway…
In the beginning, good noob items are usually a ring, and tangoes. Work your way to two bracers and boots. If you’re using clinkz, midas is nice. NEVER start off with boots as your first item. It’s horrible, it doesn’t give you regen or stats. If you’re anything other than int, noobs like sange and yasha, because the components are cheap, so it’s easy to build. It’s a pretty useless item later on though, except for some characters. It’s got a proc orb effect, so you can use it with most other orbs.