Becoming a referee
I regularly get emails from people wanting to be referees for the International Journal of Forecasting, usually with an accompanying CV. This is not how the process works.
Referees are almost always selected because they have previously written papers on a similar topic to the manuscript under review. If you want to be a referee, then write good papers and get them published in scholarly journals. Very quickly you will be invited to referee papers in the same journals. But until you have demonstrated your own research skills, no editor is going to trust you to assess the research of someone else.