I got my CBT and got a new bike few days ago I never drove anything on road before so I am not a road user. Whenever I ride my bike I am making mistakes on a road. I don't know should I quite or should I stick with it and keep riding my bike ?

Contact a Harley-Davidson dealership.  They have a relatively inexpensive (less than $400) motorcycle training course.  It will provide classroom instruction on laws and best practices as well as 8 to 16 hours of practical instruction.  Well it is inexpensive compared to what you will still owe on a new bike when you sell it to someone else.

Not knowing where you are from, you may well fight government sponsored training also.  Where I live (Illinois) it is $20 and you actually get the $20 back if you pass the course.

I understand some states have more advanced training for intermediate riders and veteran riders.  I actually think the instruction is good to re-take each time you buy a new bike to learn new laws and to help break bad habits we all get into.