If anybody want to change his profession from electronics engg to network engg what should he do or what are the courses & certification ha had to do?

1-A+

2- CCNA

then you may specialized later in career

1. computer communication networks

2.special topics in communication 

3. Telecommunication switching networks

4.cellular mobile communication 

First of all Telecommunication network is different and computer network is different and if you are interested in Computer Network  Engineer then go for Basic networking after that you can go for CCNA

CCNA, CCNP [Routing & Switching]. If you know LInux/Windows that would be a great plus.

But you will always be asked for experience. You will find a lot of people with CCNP in the marketWhere are you working right now? Is there any chance that you can move to a Network Engineer position in your own company?  

he can get the networking certificate like CCNA by cisco

He should take CCNA, CCNP courses.