You might need to slow down - the first boss Eikthyr is quite easy to beat so it is tempting to go storming into the next biome before you're ready. When you brave the Black Forrest and crypts you need the following (especially since you're a noob - an experienced player could get by on less but you want to do things safely):
1. well-established Meadows base, preferable near the Black Forrest and on the coastline. Well-established means a log wall and an upgraded workbench, plus storage and 2-3 beehives. Congrats you will now survive most raids from wildlife/ greydwarves. If you want to be extra safe from trolls, use your pickaxe to dig out a moat/trench.
2. Upgrade your leather armour
3. Don't go into a crypt without a shield and practice using it. Greydwarves and skeletons are extremely easy to stagger once you are used to the timing of a block. 1 or 2 star skeletons may kill you in crypts easily at this point, so go slowly and master blocking.
4. You need an upgraded crude bow and fire arrows.
5. Try to have the best food currently available to you.

Lastly in early game try not to go anywhere near the Black Forrest at night (just avoid being outside your base at night in general). Mobs will spawn more rapidly and are super annoying while you're trying to mine. If you find a good spot for copper and tin but you're too far from your base for comfort, again, slow down and spend a few minutes building a workbench and a rudimentary shelter with walls, a door, a chest, a bed and fire. When you have all your materials you can run a few loads back to your 'main base' for smelting/ crafting. If you are on a coastline it is worthwhile to build a Karve (boat with storage slots) as it is often much faster to move materials by sea than by foot.

It can seem a bit intimidating at first, but once you've mastered that biome and are through to the next tier of materials, the Black Forrest seems like an absolute piece of cake.