Welcome to the forum, Mobbin. You've come to the right place for help. When asking for advice it's always a good idea to tell us what engine and carburetor you have. Is it a 2 stroke or 4?
Assuming it is a Chinese 2 stroke engine the problem is very possibly what Legwon suggested. The throttle slide, or barrel, in the carburetor will go in two ways. One way it will give you the problem you're having. The barrel has two slots; one on each side. The shorter slot should align with the idle speed screw. The longer one should align with the small pin you'll see protruding from the bore where the barrel rides.
With the air cleaner removed, look into the carburetor and watch the barrel as you twist the handlebar grip. You should see it move up and down. It should be spring loaded to the down (idle) position and lift when you twist the throttle grip toward you as you're sitting on the bike.
Throttle cable tension is also important. If you didn't find the problem let us know. There are other things we can suggest.
Six days and the OP hasn't responded. Either he found the problem or didn't like the advice we gave. Too bad people can't respond to help when it's offered.