DDOS Attacks

It's been a while and I'm playing on kickback . but every time I'm about to win my game starts to disconnect and gives the error :
connection problem - auto disconnect in 25:00" and the enemy easily comes and knifes me so ez win.
I think he starts a DDOS Attack on me or the server ip , my question is :
How can I DDOS a player in CSGO (I tried and searched a lot but no tutorial was complete)
How can I prevent someone from DDOSing me in the future ?
thanks a lot guys

You can prevent DDOS by using VPN / make sure the can't get your IP (cuz its quite hard to resolve IPs thru steam unless you have some info such as skype posted there).

The logic someone DDOSes me, so will I is stupid honestly + its a crime pretty sure so don't do dumb shit like that..

So basically: don't share personal info on steam, don't open unknown links/images (really easy to get IP that way)