Can someone help me, im lost in the Campaign

Those two missions, along with the one's above them in the same column, are repeatable award missions, the adventuring gear gives a unicorn equipment chest containing a random piece of unicorn equipment (stuff you can obtain from the unicorn seal vendor).
The second mission gives you a lesser dragon hoard enchant, a utility enchantment giving you a small chance to find refining stones after a kill

Other than having the required currency as with any other campaign quest and having completed the previous part in the chain, there's no extra requirement (like completing a quest) that is required to do these, and as far as i know they can be repeated indefinitely 

Not really, unless you need ethier of the rewards theres no need to do them (my cleric is unlocking shores and has never done ethier of them, upon completing ethier quest they will just become available to do again unlike the "Assit the *" series.

So basically you can continue doing the assit the zentharim line with no need to do the quests beside the emerald enclave section unless you want the rewards, after doing zentharim 5 times the next row will open up (able to unlock shores and LoL) as well as continue on to your artifact-main hand

Hey I suggest you find someone to run dailies with because they are mind numbingly boring solo so if you.see me on I'll tag along even if I've done mine