I am working on a new project where I want to add candidates scores, there are different columns with HTML inputs that holds their performance scores at every stage, then I want to sum it up under the column TOTAL, get also the AVERAGE, and GRADE also on different columns
I intend working with HTML, jQuery and Php in getting this done, any help please?

You'll get help here but not until you first show you have put in the effort to do it yourself. When you run into specific problems you can post your questions.