Salesforce Certified Associate Certification exam is for someone who has strong basic/fundamental knowledge of the Salesforce.com platform and has up to 6 months of user experience.
If you are getting started with Salesforce Platform, then Salesforce Certified Associate Certification is the right choice. If you have good exposure or an expertise in Salesforce, then this certification will be a good refresher.
Please use the following resources for Salesforce Certified Associate Exam Preparation.
Few resources are not free.
Trailhead Module for Certification Preparation:
Trailmix from Trailhead:
Sample Questions for Reference: