Hi I just joined I am interested in mystery shopping however I didn’t know which companies are legit and real experiences from others who enjoy it. I am looking for extra income
Welcome! Take a look at the top 15 companies posted on the bottom of the page and go from there. There's a whole list of companies that you can sign up for with comments on how they pay, how the shops are, etc.
Try Marketforce for a starter. I started out with them and still do shops for them. Easy shops, easy reports, not great pay but a great way of learning.