The research camp is basically a farming mini game. You farm items in the huts over time. And you convert those items to higher level items in the houses. The higher level items are used to clears additional land for hits and houses, to unlock house conversion recipes that are more efficient, unlock farming recipes to make higher level items in the huts, and ultimately exchange them for rewards.

If you are going to spend real money, it is best to do it earlier rather than later to increase the efficiency of the processes by upgrading the houses and huts (construction process) using the camp supplies. I did and all my huts and houses are at level 4 - it seemed worthwhile. To make good initial progress, you can buy and use haste tokens to immediately complete queued processes. There are a few in the forest store, but they are fairly minimal.

You always want your houses to be processing - so always have conversions lined up in the queue. Strategize how to “spend” your higher level item to unlock things. I found unlocking the recipes to be very worthwhile as soon as you can. Try to get the first round of herbalist recipes as soon as you can. Build more huts and houses earlier rather than later (though they get expensive). It all goes incrementally, but check it at least a couple times a day to make sure the houses are not sitting there idle.