How should I add resolved tickets to add in knowledge based creation
Go to Knowledge base. Click Add new FAQ. Write a FAQ.
You cannot add tickets directly to a FAQ.
Sir can there be resolved tickets can be shown in FAQ
That would be considered a security concern, so I highly doubt it.
How can we add solution given in Ticket in FAQ
Edit the core code files to make the desired changes.
Is there any code to add there
Since osTicket is open source you are free to modify the code to suite your needs. That means you can add any code you want.