so, cloud again. we have many cloud providers, but there are 2 major ones AWS and Azure. google cloud platform is good but market is dominated by those AWS and Azure. AWS is first to enter into this, hence the advantage, but Azure is closing the gap real fast. Azure is more friendlier to normal users as well. it integrates better with other Microsoft services. in general it doesn't much matter which one to use IMHO. now, bout certificates, Microsoft announces role-based certificates recently. so before you pick the exam you think is necessary and do that one. Microsoft shifts the focus from product knowledge to a skills-based approach based on specific job roles. for example, you now have Azure Developer Associate role, then you need to pass the relevant exam (AZ 203) to be certified. exam covers the ground to be recognized as such. before that you need to pass 2 different set of exams, I guess. anyway, the basic fundamental Azure exam is AZ 900(Microsoft Azure Fundamentals) which is easy. it gives you the entry point to other exams and obtaining the role(s) required by your organization or your own desire.
there are plenty of resources available online, if you decide to sit for one of Azure exams. Microsoft its own leaning website, pluralsight, udemy etc. practice exams can be obtained as well. some good resources can be found on git hub too. there are some study guide from people who passed the exam as well. good luck