Below are some of the skills that you must know in order to become a GCP Developer:
You should be able to design architectural solutions on GCP.
It is required from you that you can serve as a GCP Architect and also as an SME in different projects.
You must have decent programming skills.
Talking about experience, you must have minimum 1 year of experience in application building for GCP.
Good knowledge of technologies such as BigQuery in Cloud, Dataflow in Cloud, etc.
You can easily get these skills and become a GCP Developer by enrolling yourself in the GCP Training Course. Also, watch the following GCP video tutorial to learn more about it: