The caves become unlocked after you get a quest from a npc that require you to get into the caves. I do not know if you need to improve your relationship to a certain point with that npc or not. There is also this one skill that allows you to order ingredients from the shops. But you need to be a friend of that shopowner before you can order from that shop. This is why relationships are important. Also there is another skiill that allows you to recruit better staff that has a requirement that your social stat has a certain value and you traint social by talking to people and completing daily quests.
Keep playing the main story. It will all become clear. :) Do research as soon as you can. Great mechanic! Sugarcane behind April's house.
The caves become unlocked after you get a quest from a npc that require you to get into the caves. I do not know if you need to improve your relationship to a certain point with that npc or not.
There is also this one skill that allows you to order ingredients from the shops. But you need to be a friend of that shopowner before you can order from that shop. This is why relationships are important. Also there is another skiill that allows you to recruit better staff that has a requirement that your social stat has a certain value and you traint social by talking to people and completing daily quests.