How do I debug a flask project using pycharm?

Xiaobai trembles and asks, how should I debug the code of the flask project in pycharm?
is that after the application starts, I click the button or link on the page, hoping to see the process and related parameters of statement execution in pycharm.
I opened the development mode of flask on the terminal, set a breakpoint, click Debug "microblog.py" (my application name) under the Run menu, and then quit the debug mode after a few steps. I feel that the service is not even up and there is no chance to open the page.

Jun.15,2021

debug = True
then debug starts

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1be6f99-31093.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1be6f99-31093.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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