For names with spaces you need to enclose the entire path in quotes as in the example. Normally the terminal will use spaces as delimiting characters, but the quotes override that so it will look for a second set of quotes to be the delimiter.
xattr -cr /file/pathway/Strive For Power.app (error, 5 values)
xattr -cr "/file/pathway/Strive For Power.app" (normal, 3 values)
A screenshot of the terminal, or error prompts, after your attempt would help diagnose your problems as the specifics are important for your input as well as the error message. You may edit out personal details, such as the username if you wish.