How to show or hide a section based on the how old is the post

I want to show or hide a section if the post is 5 days old or older than 5 days. basically i have a listings website and I want to automatically show a badge “new” on the recently added posts and I want to remove this badge if the page completed 5 days

I know that I can use string to time but how do I write the conditional value

thank you in advance