Letmeleadyou.me is one of the many websites trying to abuse the push notification function of modern browsers. The push notification feature allows websites to display notifications even if the browser isn't open. This can please someone who wants to stay on top of current news or a particular topic. However, there will always be a person trying to make easy money. One way to do that is to abuse the push notification function to bombard the user with unsolicited materials. For Letmeleadyou.me and other similar websites, these materials are advertisements. Whoever is running these websites gets revenue for displaying the advertisements.
The most common businesses willing to go for this marketing kind are adult websites and online gambling websites. It's not rare such advertisements leading to sites pushing fake update notifications that may result in the download of Potentially Unwanted Programs (PUPs) or even malware. There also are cases where legitimate marketing campaigns end up showing in the push notifications of such websites, usually due to subcontracting.