Domain propagation is the process of updating all of the DNS servers around the world with the new information for your domain name. This includes your domain name server (DNS), your internet service provider (ISP), and any other DNS servers that may be caching your domain name information.
When you make changes to your domain name, it can take a few minutes to 48 hours for the changes to propagate across the internet. This is because your domain name server (DNS) needs to update its records with all of the other DNS servers around the world.
The time it takes for propagation to occur depends on a few factors, including your internet service provider (ISP) and how often they update their DNS records. Some ISPs update their records more often than others, so you may see the changes reflected on your computer sooner if you have a different ISP than your friend.
If you're trying to access your website by its domain name and it's not working, don't worry! Just wait a few minutes or hours for the changes to propagate to your ISP. In the meantime, you can still access your website by its IP address, which is listed in your account information email.