How to exactly add a widget in Qt Designer??

[Guohao91]

Hi, Mr. Clark
I am a newbie for Qt designer, I am using Qt5. Please forgive me to post this question. I find out some ways online demo how to add a widget in Qt Designer, but they don't work on my computer.
Can you put some details on here describing how to add a new widget in Qt designer?

[Guohao91]

so this the step I stopped by....I don't know which file should be put in the Executable blanket?
Can you tell Mr. Clark?