Hey there saif-blankspacei,
It's always a pleasure seeing new faces in the QuickBooks Community! Thanks for reaching out to us here! QuickBooks Online is a great tool that helps keep your books balanced. It's important to have the correct information in your customers profile. I can provide some information.
At this time, there isn't a way to completely delete a customer within QuickBooks. However, you're able to make them inactive. By making them inactive, they will no longer appear in lists and menus. For your reference, Here is an article that will help you manage your customers. I recommend reading through the article so that you can get a good idea of what you can do in your customers profile.
If you have any other questions, feel free to reach out here.
