I just debugged the code and found out that table names are case-sensitive.
This topic helped me show the errors on page and then when i reloaded the page and it show error that it couldn’t find any tables named PRODUCTS so i found out the tables name in php code and in Uppercase and in database it is lower-case . I changed the table name in database to uppercase and now it works like a charm.
Thank you Admin for taking out time for this and replying me, Hope you have a good day :).