Im not really sure how to get more gold, the only way i can think of is doing missions and by opening chests when you explore. Help please, thanks.

This guide can explain you in depth all the possible options but yes, missions are the best way to get gold until you unlocke the lost grove. Selling unwanted items from the festival can also help you get more gold.

As for mission themself, you get more gold if you send the right kind of pet into them, this guide should be clearer on what pets you want/dont want to send into mission to get the full amount of gold in the end. Keep in mind that mission pets and party pets should never be the same as this prevent you from exploring until your pet come back from mission. ^-^

Thank you so much, that was helpful :)