Activities

If you aren't forced marching, each party member can do an activity. If you are stationary, this check is made with advantage. If you're trained in both skills, pick one and add the PB of the other
Scout (in terrain) - perception or nature: you head out in front of the party or move on when camp is made. You look for trails, landmarks, high grounds and other things that might help the party find their way and stay undetected.
DC10: no chance of getting lost
DC15: no chance of being detected 
DC20: +10km speed
Forage - survival or nature: you use your craft and knowledge to find food for the party. Fish in the nearby river, hunt game or snare rodents, pick the non poisonous berries. This is the base check in normal terrain. Other terrains may increase this DC.
DC8: one ration card and drinking water
DC14: two ration cards
DC20: four ration cards
Keep watch - insight or perception: in the dead of night there needs to be someone who watches over the sleeping. You don't do it alone, but you are in charge of securing the camp, setting a schedule and taking the midnight watch.b
DC10: can't get surprised by nightly attacks 
DC15: escape option: take a DC10 Con save or exhaustion instead of combat
DC20: get surprise round on attackers
Campcraft - performance or survival: you bend your skill towards bringing the party comfort after a long day's march. You cook a warm hearthy meal or perform a story through song and verse. 
DC12: one guaranteed success on the next exhaustion DC
DC16: - 1 exhaustion level
DC20: immume to exhausion the next day
Improvise - depends: convince the DM with a detailed description of what and how you're going to contribute to the situation