My question is to know if I can just enroll for the exam and pass them, or there are some other requirements I still need to meet.There are no training requirements for the MYSQL certifications. The only other 'requirement' is to set up your Certview account before scheduling the exam. Otherwise you won't be able to access your results until the account setup has completed.
Is there any difference between the oracle web account I have and the certview account?Probably, depending on what you mean by Web account. The Certview login (and account creation) link is below. Try to log in. If you can't then create an account. The password will be the same as your OTN account (i.e. username '990902', password [whatever]). The two accounts are linked, but not the same thing.