You can usually use light coconut milk in recipes. However, when we do call for full-fat coconut milk, it’s because the extra fat is crucial to the outcome, so do not substitute it.
Though you can now find coconut milk in the refrigerated plant-based milk cooler, what you want is the stuff in cans. Most of the refrigerated versions are diluted with water (and filled with stabilizers and whiteners). They’ll be fine in a cup of coffee or a bowl of granola, but they won’t give the coconut flavor and richness you want in a recipe.