Do I unlock new spells as soon as they become available, for example, class spells, or is it better to completely level one spell before unlocking a new one? I haven't been able to find any information on this at all.
(TLDR: unlock new things so are levelling as much as you can at once)
In practice if you ignore all the mechanics and just unlock the skills you want to use you'll end up with something in the right ballpark, which I assume was the intention of the system in the first place.
If you are optimising then then as you do the tutorial or straight after unless you are working on a specific build walk out of the door and kill something (even a goat) with two handed, dual wield, sword & board, destruction staff, restro staff and bow. That enables all the weapon skill lines. Pick up and wear 3 pieces of light, then medium then heavy and it'll unlock all the armour lines, then put on whatever you actually want to wear.
When you get experience you improve the skills on your front bar at that time (or you only bar before level 15), so you want to unlock one of each class skill lines and a weapon skill line of choice asap and put those on your bar so you are always levelling them. You can even park skills on the bar to level them, and some people put stuff on the bar when handing in quests.
In addition you want to wear at least one piece of each armour type whilst levelling (ie light medium and heavy) as that levels all the armour skills.
If you are working on a specific build then obviously you can work down the skill lines required in a very targeted way but if you are new to the game I would suggest you take a more general approach because you are likely to find what works for you and fits how you want to play over time as you wander around the game doing stuff.
There are also a bunch of skills that level by doing stuff
- do the mages guild questline, collect books and do the daily quests, especially if you are magicka, and also if you have companions to level up
- ditto the fighters guild
- when you meet it ditto the undaunted daily delve quests, until you are big enough to do pledges
- when you hit level 10 do the cyrodiil tutorial to unlock those skills even if you will never do PvP, because some are very very useful in PvE like the passive for mount speed
And there are certain things tied to real world time that you want to start early
- horse riding
- learning traits by deconstructing spare gear
And collect skyshards, you can never have enough skill points in the early days!
Wow - thank you for such a detailed reply! I think where I'm getting confused is about specific skill lines. Say I have a spell from class line A on my bar, and a new spell in that line becomes available. If I learn the new spell and put that one my bar instead of the old spell, will both spells level up as I gain XP? Am I levelling up the line, or the specific spell?
Short answer, you can open and level any skill you want as you can always pay gold to go back and respec if you want a change.
Long answer, check out some guides on what skills are necessary, optional, good, bad, meh for your build. Alcast, Tamriel Foundry, Xynode, Hack the Minotaur, etc.; there are quite a few sites out there. You don't need to copy the build, but they will show you what skills work for what builds. That way you won't waste time levelling up something you won't use. These sites can also help with CP allotment.
The main reason for this is that there are skills that are role-oriented for tanks, DDs, and healers that really only work well for them. Another reason is that there are skills and morphs that are either PVE or PVP centric. The game does not really explain this at all, which is why these sites help.
Remember, its a game. Have fun. Play how you want to play, at least until you move into vet group content