Hello Pavankumar,
Regarding your questions:
The difference between free edition and CE: "Free Edition has been designed and extended to include full access to the Data Intelligence Platform. It provides an easy-to-use environment where you can build AI applications and agents, collaborate on data science and ML projects, experiment with AI models, create interactive dashboards and Genie rooms, and much more."
1. Yes, there is limitation on compute resources. (e.g. you can create only 2X-Small SQL warehouse)
2. Most likely
3. Go to this link: signup , write down you email, login, and everything will be setup for you automatically and you will be able to use the free edition
FYI for CE: "Existing users are encouraged to try out and use Free Edition. Access to legacy CE accounts will continue to be available for the remainder of this year."