If you are trying to equip the pickaxe, while you have mouse over it, you can press R (I will add dropdown menu in the future). It's a bug that you can assign equipment to the actionbar (fixed now)! The world edge is no longer limited.
And also the grass is 'consumed' but I do not have an animation for that yet. You can eat the mushrooms or cookies too to gain some health during fights.
Once you level up, you get attribute points and skill points (every 3 levels). You can spend the prior in the stats menu on attributes. For example strength will increase health and melee damage.
As for what there is to do atm, not too much besides removing blocks, placing them and killing monsters! You can talk to npcs, gain quests, and explore the world. However I'm still working on making the world more diverse by adding content.
Soon I will add dungeons! Also your english is fine! :D
Edit: Yes sorry, night is better optimized now!