Internet connections shuts down

Greetings. I do not know how to start since I don't have idea when and why my internet problems started in the first place. I was doing perfectly fine til I have this problem which sucks my life literally since I use this thing for my work. Going back, I tried everything that I can do trying to save my Internet connection and like every youtube tutorial on how to fix it I think I watched them already but so far it's no help. I can manage to be connected on WIFI which I am using from the very start, I can use Skype just fine and I have the chance to browse the net for like 5 minutes then after that it will appear that there is no internet connection. Like what the F? I tried the CMD thing and Ip reset fixing Adapter setting, also the firewall for my Antivirus but nothing happened. And so I am planning to have the item reformatted or reprogram I don't know. What I want to know if I do such would be 100% gonna work? Like i don't care if I will lost some file as long as the internet will work I am okay with that. hope to get answers from you guys.