Question: I want to learn how can I protect my PC from getting hacked in order to protect myself from cyberbullying. There is an intruder who has hacked my system over the last 4 years. 

He has hacked my all emails, websites I log on to and whatever when it is related to me being online. He has a team of friends and has professional links all over the world. 

When I make an email from another computer, I don't know how he comes to know about it but he knows my minute credentials of my account information. 

When I go on certain websites my internet suddenly disconnects. I have to connect and reconnect my modem at least 200 times a day.

Even if I choose to take legal action on him,he would be locked up for some 6 months in a prison,but I have other plans for him(sorry for openly threatening). 

I haven't used any of my emails (except reading) from last 3 years,he knows every website I visit on and that is how he uses me.

And I know all this, because he has accepted all these things over our chat.

Someone has advised me that I will have to become hacker to prevent myself. Is there any way I can consult a good security expert or an institution,where would I find it.

I live in India.

Answer: 
1. format your system
2. get an Antivirus and Firewall
3. secure all your wifi networks
4. make a new email address or change EVERY detail in your email account especially password and security questions. Your password needs to be strong.
5. file a complaint with your local police office
6. Don't share any details with anyone.
7. stop doing drugs.
You really do not need to hire security professional in this situation. Since this "hacker" has accessed your email account[s], bank login, and knows what websites you visit then he either has infected one of your computers with a trojan/backdoor/keylogger or has hacked into your wifi and is sniffing your traffic. Answer these questions for me:

1. What type of security do you have on your wireless network?
2. Is your firewall active on all of your computers?
3. Do you have a commercial antivirus installed and actively monitoring/protecting your computers?

I really do not know what sort of problem you are facing without knowing the answers to these questions so if you would please respond to them I can help ypu better. There really is no need to learn (in detail) hacking in order to mitigate threats.