I am a newer Qt Programming. I want to make a program with 1 lineedit and 1 textedit. when i write a command bash (example "man cat") and press enter, then textedit show output from this command (from this example, then text show manual about cat). How to solve this problem ?

how to call other program from qt. example i want to open gimp program from Qt program. what command to call other program.
thank for your attention