Emmanuel ,
you have just started learning the "python for beginner" tutorial. so at this stage you may only solve simple exercises. the "credit card validator" is in level of difficulty < medium >.
so this means you should continue learning and practicing, until your level of knowlege equals the level of the exercise.
be patient and do not step forward too fast. it takes some time and effort, but then you will soon be able to complete tasks like this.
happy coding and good success!
