I am seeking a clarification. According to fiqh, it is essential to ensure that during ablution water reaches the skin. Can you please confirm what this means?
Usually after washing face with soap, after sometime, there forms a layer of oil on skin. Should this oil be considered a barrier in water reaching skin or is it ok to consider this oil as part of skin thus water can be poured and spread over face or hand to meet conditions of ablution.

Please confirm

If you use a water based product like soap, and then do the wudhu, then it is fine.

If you use an oil based product, then it would be considered a barrier.