How can I turn on a healthbar for my Hunter Pets? One that will stay above his head and follow him around?
Go to Esc (to get up the ingame menu) → Interface Options → Game → Names.
Under the Nameplates section, check “Friendly Units” so friendly nameplates are shown, and make sure “NPCs” is ticked in the unit list below it. Pets count as NPC-type units, so this makes a nameplate appear over your pet and follow it around.
If this doesn’t work for you, post again and we’ll figure out why.
As a newcomer bonus, let me recommend this video
https://www.youtube.com/watch?v=zyqj414Se1Y
which is huge, but broken up into 1-2 minute chapters, so you can go straight to the section you want.
Most experienced people will use addons to show unit frames and healthbars, and each addon has its own way of controlling what is shown. You will find sections on addons in that video.
When i press esc there is a options button, no interface options. when i click options and go to the interface section under gameplay there is no game names options or anything like that. only display section, quests, raid frames and arena enemy frames sections. i cant find it anywhere
As far as I can tell, the only way to do that for your own pet is to use an addon (like Plater or Weakauras). The only options I found in the interface menu were for names.