I am using sonarqube community edition. And it just able to scan the main branch of repo. I just want to scan other branch also rather than only main in community edition.
Branch analysis is part of our Developer Edition.
See more here: Try Now Developer Edition | Sonar
If you want to try, just request for a free 14-day trial on our website !
Hope this helped,
Carine
Welcome 
as Carine already wrote, the branching feature starts with Developer edition ($) and upwards.
With Community Edition you must use one Sonarqube project per branch, that’s the old way before Sonarqube introduced the branching feature.
The sonar.projectKey has to be unique, i.e. if using a Jenkins pipeline you may use
com.foo:bar-$BRANCH_NAME as value.
Gilbert