In fact, it is not a big problem to have no foundation. People never have a foundation, and not all of them are proficient in a certain technology. The key is to rely on personal efforts and learning mentality.

I was also CCIE in the zero-based exam before, and spent more than nine months preparing for the exam. Looking at the certificate I got now, I know that the original efforts were worthwhile.

Prepare suggestions:

Specific to the exam, in fact, you still need to go to institutions to study, and there are question banks, such as written exams and all-English exams. Even if you study well, your English is not good.

Find a better training class to go through the class systematically, read several reference books carefully and do more experiments.

You must persist mentally, because preparing for the exam is really long and takes a long time. Therefore, we must persist and fight this war with our hearts.