I'll expand. Using this guide for skills list:

http://elderscrollsonline.wiki.fextralife.com/Animal+Companions+Skills

1. As a stam character, you want to unlock and level and skills that morph into stamina versions. These are typically your attacks...I won't list them, if they cost stam you'll use them. Magic based skills are still important. These "magic dumps" can allow stam characters to cast buffs, shields, etc without sacrificing their stamina pool. Examples are the netch, bird of prey, green lotus, etc. These cost magic, but deliver buffs good for stamina characters.

But generally, there are so many skill points in the game that you could unlock every class ability and play with them if you like. But if you want to save time and money, avoid ones that deal magic damage, as well as fire, frost or shock, and look for ones dealing physical damage, or disease and poison.

2. Most morphs offer an obvious choice, like Dive, which has a stamina option and a magic option. As a stamina character, you want that stam option. Others are less obvious. Don't stress...pick the one that sounds best and play with it. Down the road, if you want to undo morphs and get the points back you may. My super vet only pays 1500 gold to recast a gazillion morphs, so it's not expensive. When your character is young, it's a couple hundred, no biggie.

As you level, keep note of which skills you use a lot and look up what the alternative morphs are. If something seems like it might play better because you've learned the mechanics better, go recast and try out the alternative. As a new player you'll likely recast several times through your character's life...don't hesitate to do this often.

3. Stamina Wardens may level all four physical weapon lines. Dual is very important, 2h is important, bow is important. 1h/shield is the least useful...it's a very defensive line and stam Wardens needs some weapon attacks...feel free to set this one aside unless you want to play around with it.

As a rule, dual wield skills pump out single target damage while offering some sort of buff, 2h is about raw power and multiple targets, and bows offer range and DOTs. You'll be using them all in your characters life, feel free to unlock and play around with every single skill in these lines.

On a side note, level both medium and heavy armor. You'll probably wear a blend of differing pieces at times, so try to wear 4/3 or 5/2 now and keep them leveling up.

Some addl tips:

- everything Nestor says is 100% correct, so I won't repeat that, lol.

- don't stress too much about leveling skills, other than practicing the general guidelines. When you get to vet, there's a "catch up mechanism" called enlightenment. This delivers you a daily dose of 400,000 xp at 4x the normal rate. Levels 1-50 entail about 3 million xp all together...this is what is applied to level your skills. So at vet level, you earn about as much xp in a week as everything you earned all together as a nonvet.

Long story short, any skill lines or abilities that get behind are very easy to level as a vet by earning your enlightenment xp with those abilities equipped. I just leveled my stam Wardens 2h. He'd never used one before...in a week of enlightenment I had the line to level 45, with every skill morphed and at morph level 2-4. And I wasn't playing him hard, just an hour a day running some delves and dolmens he needed.