Hi Zheng,
Thank you for your message and sorry for the late reply. For quick conversions you can use an online converter like
https://www.andre-gaschler.com/rotationconverter/
If you are interested in the mathematics of the conversion or how you can implement a code to automate the process, Wikipedia has a really nice article:
https://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles
Again, for automating it there are already very fast and efficient built-in libraries that you can use (
Python,
C++, etc.).
Best,
Srdjan