how does commercial bank create deposit?explain

Elis, this topic has been extensively covered in the study material for Economics that's available on our site. Follow the link given below (under the topic- 'The process of creation of money'.

https://www.meritnation.com/cbse/class12-commerce/studymaterial/economics/introductory-macroeconomics/money-and-banking/341_1988_5841#slide4_functions-of-commercial-bank-money-creation-by-commercial-bank