When it comes to making a peanut butter substitute, there are a few things you need to keep in mind. The first is that peanuts and peanut butter have different consistencies, so you will need to adjust the amount of liquid you use accordingly. Peanut butter is also generally much sweeter than peanuts, so you may want to add a bit of sugar or honey to your substitute mixture. Finally, keep in mind that peanuts contain more fat than peanut butter, so your substitute will likely be higher in fat as well.
With all of that said, yes, you can use peanuts instead of peanut butter in most recipes. Simply grind up the peanuts into a paste and then add the appropriate amount of liquid until you reach the desired consistency. If your recipe calls for chunky peanut butter, you can leave some whole peanuts in the mix. Just be sure to taste your mixture before adding it to your recipe to make sure it meets your expectations!