Solid mode vs Textured mode (faces not displayed)

Hello

I would like to ask for help: I’m having difficulty with blender meshes: When I see my object in edit mode, it is like this:

However, when I switch to texture, to add texture to the faces, it scares me like this:

Is anyone able to recognise problem ?
Many thanks in advance

My best guess is some of the normals are flipped. In edit mode try selecting everything and hitting Ctrl+N.