Hi Ashok,
If you're just starting with Azure, I would recommend to start with Microsoft Learn. They have up-to-date content on Azure divided into different learning paths. To start with, go with Azure Fundamentals - https://learn.microsoft.com/en-us/learn/paths/azure-fundamentals/
Along with Microsoft Learn, please refer to Microsoft Documentation on Azure which is the single source of authority/truth for everything in Azure. Check this out - https://learn.microsoft.com/en-us/azure/
Then there are enormous number of courses on Azure in all the leading online training portals including Pluralsight, LinkedIn Learning and Udemy. You might like some courses on YouTube as well. Microsoft has partnered with Pluralsight to give access to 200+ Azure courses for free. Please check it out here - https://www.pluralsight.com/partners/microsoft/azure
I have published a video tutorial on "Getting Started with Microsoft Azure". You can check it out here - https://vaibhavgujral.com/2020/04/28/global-azure-day-2020-getting-started-with-microsoft-azure/
Lastly, Microsoft has divided Azure Certifications based on different roles. I would recommend to start with Azure Fundamentals Certification (Exam: AZ-900) which covers the basics of cloud computing and Microsoft Azure. If you have past experience in Application development, "Microsoft Certified Azure Developer Associate" certification might be the right fit for you. Check out the different Azure role based certifications here - https://www.microsoft.com/en-us/learning/browse-all-certifications.aspx
There are a variety of courses available online for certification preparation. You can also buy study guides on Amazon and other book stores. Then, there are some study guides published by people (including me) who have appeared for these certifications in the past.
I have published few posts on Role based certifications as listed below -
https://vaibhavgujral.com/2019/11/15/getting-started-with-your-preparation-for-azure-certifications/
I hope this helps!
Regards,
Vaibhav Gujral.