The AWS Certified Solutions Architect Official Study Guide for the Associate exam will be very useful for preparation. This book will give you very good insights regarding the subject through expert content, real-world knowledge, key exam essentials, chapter review questions, access to Sybex's interactive online learning environment and so on so forth. This official study guide covers exam concepts and provides a key review on exam topics. This guide covers the following topics.
Mapping Multi-Tier Architectures to AWS Services
Understanding managed RDBMS through AWS RDS (MySQL, Oracle, SQL Server, Postgres, Aurora)
Understanding Loose Coupling and Stateless Systems
Comparing Different Consistency Models in AWS Services
Understanding how AWS CloudFront can make your application more cost-efficient, faster and secure
Implementing Route tables, Access Control Lists, Firewalls, NAT, and DNS
Applying AWS Security Features along with traditional Information and Application Security
Architecting Large Scale Distributed Systems
Understanding of Elasticity and Scalability Concepts
Understanding of Network Technologies Relating to AWS
Deploying and Managing Services with tools such as CloudFormation, OpsWorks and Elastic Beanstalk.
At the time you have is very less, I feel you can follow this book and you will go through the subjects and then I hope you will be successful.