Can I completely remove cafe au lait birthmarks with a cream?

Cafe au lait macules are birthmarks and are benign. Laser treatments can be used to treat it. There are different lasers that can be used. However, usually multiple treatments are required and complete clearance may not be achievable in all cases as treatment response may vary with individuals. Furthermore, the recurrence risk is also very high. For these reasons, you should discuss this carefully with your doctor before starting treatment. You can see a dermatologist/ aesthetic GP or doctor experienced in laser treatment.

It does look like a bit of hypopigmentation and you are correct that it is difficult to treat (most of the time we will have to rely on our own cells to re-pigmentate the area unless you explore other medical repigmentation options). I would suggest laying off the “gentler” laser treatment that you have every 2 weeks for the hypopigmented areas. That being said, the “stronger” laser treatment that you have every 6 weeks should be able to treat the Naevus of Ota (to avoid the hypopigmented areas). Usually, treatment of Naevus of Ota does not leave a white patch.