What's needed to be approved for a good PhD in Mathematics?

[arsenalvg]

I’m a Vietnamese First-Year Mathematics student who really wants to pursue a PhD in Mathematics.

1.  What's needed to be approved for good PhD in Mathematics? (in detail). I know that it must need a IELTS/TOEFL degree, GRE, 3 letters, ... But at which score I will get approval from a graduate school in Top 50 over the world. How can I get that three letter in the best way I could?
    
2. Give me as many as advices, experiences you have on what I need to do now to be a strong applicant in the future. And if possible, tell me more about your story in pursuing a PhD in Mathematics. Tell me more about your research, what did you do in your undergraduate... Suggest me some propriate universities, Professors, the corresponding branch in Mathematics that you've taken or know...
    
3. Sorry if the question posted somewhere and if it's too general and too much. Thanks a lot. Please help me. : D

Mathematics Lover.

 

Edited March 11, 2020 by arsenalvg