One of the first things we'll do after creating an AWS account is add users and groups via the IAM console. We will initially do this as the "root" account user. But be careful -- root accounts are not restricted in any way. Therefore, I strongly recommend following the Security Status checklist FIRST when visiting the IAM console.
The AWS Certified Cloud Practitioner exam is the most basic AWS certification you could obtain. It certifies that you have a basic knowledge of the core features and benefits of AWS. It's a great kickoff point if you want to work towards other AWS certifications.