Got copper ingots, got a forge. can only forge copper knife??

[MonoV4]

That's it? don't know how to go about upgrading the forge table to unlock further tools? I'm to underpowered to take on the second boss.

[Budnick]

get some tin. you can find it by the water in the black forest. 2 copper 1 tin = bronze

[LunarMorph]

Equip your Hammer, right click and look under Crafting Tab...you will see items you need to upgrade the Forge Bench.

[RustyBeans]

You need to find Tin ore to combine with the copper ore to make Bronze Ingots.

[Fred]

Need dat tin boi

[Lowcost]

Find tin near water in blackforest, make bronze with tin and copper and you'll unlock much more

[-={0$1k}=- Isobar]

Copper+tin=bronze. That makes you better gear

[Morbs]

I'm assuming these 6 posts above me will say the same thing but...

Combine tin with your copper at the forge to create bronze.
Tin is found along the shores of the black forest.

[Luke the Lucky]

One tip though is don't focus too much effort on getting bronze armor. The tools and weapons are needed but upgraded troll armor got me through to iron.