Interview suggestion

Hi

I have 5 years experience . In that 3.10 years in cloud and 2 years in app support. I need to move to development in spring boot and java . I am average in problem solving. I am in bench for 90 days. The development team not accepting becoz of lack of handson. Other service based companies ask for spring boot and microservices coding interview . What are the websites we need to refer ? Is it ok to go and attend them ? Else join any project here and prepare for them. I am not getting calls from any product based companies.