Hey we all have to start somewhere.
What I really need you to do for me is to go to a store and buy some cloth hand wraps, then go to YouTube and watch a video of a boxer wrapping his hands until you can replicate, it's pretty easy and will save your hands.
If you want to work the heavy bag have a set ready to do before you start. I recommend this for all beginners.
Before you start you are going to need to know these strikes. Jab, hook, straight, leg kick, body kick.
These are bread and butter strikes. Once again go to YouTube, watch a boxer/kickboxer perform the punches and kicks.
Jab x 50/25
Jab - straight left x 50/25
Jab - straight left - leg kick x 50/25
Jab - straight left - right hook x 50/25
These are just some basic combos, go slow and focus more on technique than just throwing with all your might. It is easy to fall into bad habits without someone watching. But baby steps