OP:
@JASFLALMT is exactly right. You are on a discussion forum and the perfect place to learn about mystery shopping. The first thing you want to do is read about it - the messages in the New Shoppers area will tell you everything you need to know to understand the industry. Then, at the bottom of this page, is a link to about 200 companies. Sign up for them - a few at a time, starting with the ''15 Most Discussed" and find their job boards. Request a shop and, with some luck, you'll be assigned. Once you are established, you will get a very high percentage of the jobs you request - and will often be able to simply assign yourself.
As you have questions, feel free to ask them on the forum. There are some very experienced shoppers who frequently offer help here.
Hard work builds character and homework is good for your soul.