I want to create a custom report using the custom table section in the admin under the reports menu. COuld you please help me out.
I have found one extension created for custom report. It contains sample code with needed file and uploaded on github.
You can look at below URL. https://github.com/yash7690/magento2-customreport
free extension https://landofcoder.com/magento-2-advanced-reports.html
I used this module https://github.com/degdigital/magento2-customreports/ and customize to my needs.