I followed some of the references people added.
Create a material, add a material instance to your actor.
In the material add a texture as a variable.
Apply the material instance to the correct mesh.
Create a texture trough code, modify the pixel values based on colorformat. //here i get a R16 G16 even if i try to make it a R8G8B8A
Trough the material Instance fetch the texture variable and set the texture value to your created texture.
I managed to get it working with random color for a while.
But trying to make the material white, made it end up with Green and black lines.
Sometimes the random texture would have a black square in the middle.
Code samples would help a lot or modern references.