As far as targeting goes, I've been able to figure out using the F keys for party members, but my friend was trying to teach me how to target party/alliance members through the status windows on the side, except he's playing this on XBox so he couldn't help. I can't believe that I'm having trouble with something that simple, but I've had to learn a lot on my own so far. =/
Are you playing on PC? The thing he's talking about for targeting through the party list on the side of the screen is <stal>, if you use that in a macro such as "/ma Cure <stal>" then it'll give you the pointer in the side bar. This is a very popular targeting method for healers but personally, I've always felt it's only necessary if you're on a console or if you're somewhat lazy. When you have a full keyboard at your disposal, and especially if you use Windower, there are many faster ways to target people.
For example, you already mentioned F1-F6, those are pretty much the fastest way to target party members. If you use Windower, you can also use Ctrl + F1-F6 to target members of the top party in the alliance, and Alt + F1-F6 to target members of the middle party in the alliance. Another way to target quickly if you see the person on the screen is to pivot your camera around so that the person is just to the right of the center of the screen, then hit F1 to target yourself, then hit Tab to cycle to the next target. Lastly, of course, you can also type "/ta <name>" to target the person.
As you can see, I use a lot of different methods to target people, often just whatever feels fastest at the time. If you are like me, you'll probably want your macros to be <stpc> instead of <stal>. <stpc> gives you a subtarget cursor that scrolls through other players only (skips monsters), and it works really well with other targeting methods because if you target them first, you just hit your macro, then hit Enter to confirm target. I also like this because if you know you need a spell before you need it, you can target them first and get the subtarget up and ready so that all you have to do is hit Enter when it's needed. You can't always do this with <stal>, if you have an <stal> macro and you try to target someone outside the alliance, it won't let you cast on them.
I know that I can skill-up curing on my own just through sheer repetition of casting on myself, but what about Divine? I have it up to about... 180ish, I think. I did some skilling up at Eldeime when I was at capped at lvl 55 before, and then jumped the rest to where I'm at now through exp parties.
It's hard to skill up divine alone, but there are ways you can do it in parties. For example, cast Flash a lot. It generates a lot of hate, so don't cast it on the pull, but after a few blows are exchanged throw it out there. Also, if you end up with extra time during combat, throw out the occasional Banish as well.
If you're desperate to skill up solo, you can try this: Find some monsters that are fairly weak, but strong enough that you still gain skill ups pretty fast, and cycle through Banish > Flash > Repose > wait for Flash/Repose to be up again before waking the monster with Banish. This might be pretty slow.
Lastly, there's also skillup food. "Pitaru" is the name of the magic skill food, although there are different ones for your target skill levels and I'm afraid I don't recall which are used for what. You should be able to find info out there. If you eat the correct one, you'll gain skillups more frequently.