How can we separate wheat and red chillies?

Sieving - Sieving is a method in which fine particles are sieved through holes of the sieve while the bigger impurities remain on the sieve.

Example: Sieving is used in a flour mill to separate impurities like husk and stones from wheat before grinding it.

The Sieve has minute holes in it to allow the passage of small substances.

Wheat is a very minute particle. In order to separate Wheat and chilli one will need a sieve that has very minute holes so that the wheat is passed through it but chilli remains in the sieve.