How to separate the object to smaller units to give different materials to the different parts?

Question

I have been trying to create a closet in Blender 2.8 and giving materials to the frame, the doors and the handles, but whenever I try to assign a material for example to certain doors, the whole object got selected. My first idea was to use "Mark Seam" to use it as "boundary" of the different materials, but it didn't work, then I used key P to make separations in the object, but it - although separates the object by selection - still didn't work, it keeps using the whole obejct. Can anyone please help me? Thank you.

Answer 1

Materials are assigned on a per-face basis. You can think of assignment to an object as a convenience function: 'Assign to all faces in the object's mesh'.

Assign to individual faces in Edit Mode. Add slots using the '+' sign next to the material slots panel. Select or create materials to occupy the slots.

Select the slot. Select the faces. Hit 'Assign'.