A material is chosen because its properties match what the job needs. Copper is used for electrical wires because it is a good conductor of electricity and can be drawn out into wires. The wires are covered in a polymer, which is an electrical insulator and is flexible. Glass is used for windows because it is transparent, hard and does not react with water. Kiln linings are made of ceramics because they have very high melting points and are poor conductors of heat.
Saucepan handles are made of a thermosetting polymer because it does not soften when heated and it is a poor conductor of heat. Aircraft use aluminium alloys because they have a low density and resist corrosion, and bicycle frames can be made of carbon fibre composite because it is strong and light.
To select a material from data, list the properties needed, use the data to rule out any material that fails a requirement, then compare those left. Cost matters too, so the cheapest material that does the job is often chosen.
You may also need to estimate sizes. An atom is about 0.1 nm wide (1 × 10-10 m), and a nanoparticle is 1 to 100 nm across (1 × 10-9 m to 1 × 10-7 m). A nanoparticle 5 nm wide is therefore 5 ÷ 0.1 = 50 times wider than an atom.