Valheim drops you in a field with nothing and explains almost none of it. Here is what actually matters early, in the order it matters.

1. Eat three different foods, always
With nothing in your stomach you have around 25 health, which is one hit from most things. Three different foods fill three slots and each adds to your maximum. This is the single biggest thing new players get wrong. See the food guide for what to eat.
2. Get Rested before you leave
A fire, a roof and somewhere to sit gives you the Rested buff: better health regen, better stamina regen. It costs nothing and you should never travel without it.
3. Make these, in this order
Hammer and a stone axe.
- A
Workbench, with walls and a roof over it or it will not work.
Flint axe,
Flint spear and a
Crude bow from flint by the water.
- A
Bed and a
Campfire with a smoke gap.
4. Do not fight what you do not have to
Early on, running is usually correct. Greydwarfs at night come in packs, and a troll will end you instantly. There is no honour system here.
The three things that kill new Vikings
- Chopping a tree and standing where it falls.
- Sealing a campfire indoors with no smoke gap.
- Wandering into the Black Forest with no armour.
5. Build somewhere sensible
Flat Meadows, on the coast, near the Black Forest. The base location guide explains why each of those matters more than it sounds.
6. Then kill your first boss
Two deer trophies summon Eikthyr, and his drop is the pickaxe that unlocks mining. Until you have that, you are stuck. After it, read the progression guide to see the whole road ahead.
Happy adventuring!