Learned to build some more complex models, unwrap UVs and then map textures.
Keypad
The keypad is modeled with basic shapes. After marking seams, the surface of the keys are unwrapped so that all the keys can use the same texture image for mapping. The green indicator is rendered using an emission shader.
Keypad Blender Project:
Abacus
The abacus is also modeled with basic shapes by loop cutting, extruding and beveling, and using the subdivision and array modifier. Rendered with pure color texture and the reflections are reached through roughness adjustment.
Abacus Blender Project: