What is the difference between microwave, grill & convection?
How to decide if the food preparation requires the microwave, grill, convection or combination thereof?

Hi, kumarpankaj78!

The best way to find out the differences between those types of food preparation, would be to look up the definitions of each of them. If you click on the links below, you'll find the definitions.

Microwave Cooking Definition - Google Search

Grilling Food Definition - Google Search

Convection Oven Cooking Definition - Google Search


Whether food preparation requires a certain type of cooking and/or heating, would be dependent on what is required according to a recipe and/or personal preference and taste.

What types of food preparation are they about which you're looking for information concerning the preparations thereof, please?

Thanks!

Convection ovens/fan ovens augment a traditional oven by circulating heated air using a high temperature fan. By moving hot air past the food, convection ovens can operate at a lower temperature than a standard conventional oven and they can cook food more quickly.

A grill is a device or surface used for cooking food, usually fueled by gas or charcoal. Grilling is a form of cooking that involves direct heat.

A microwave oven, or microwave, is a kitchen appliance employing microwave radiation primarily to cook or heat food. Microwave ovens have revolutionized food preparation since their use became widespread in the 1970s. However, a microwave is limited because it cannot "brown" food and heats unevenly.
A convection oven is best for baking.
A microwave is perfect for reheating leftovers and popping popcorn.
And a grill is ideal, in my opinion, for cooking meats.