Fortunately, anyone can change their web hosting provider regardless of their technical knowledge. While you can migrate your site to the new provider on your own, less tech-savvy users can take advantage of the free migration services on some of the other servers. Switching between web hosting providers isn't a big hassle. There are some potential problems, but nothing that can't be resolved in a timely manner.
Some will generate a temporary URL from which you can view your website, while others will have a test environment where you can play with your website and change it while viewing it. They're not the same thing, of course, but you can contact them and ask them if they're also experienced in switching web hosting; they'll likely have the experience to help you. The change in the hosting environment can cause this to happen, and it's not unlikely that you'll see some 404 errors (not found). If your host is difficult to contact, offers inadequate solutions, or doesn't offer support in areas directly related to your hosting account, consider switching to a new provider.
Moving your website to a new hosting provider isn't an inherently difficult process, but it involves many steps that must be carefully completed for your site migration to be successful. This way, you can access the files on the new server through the old domain without changing anything for your visitors. Fortunately, this isn't the end of the world; people change their web servers all the time, for several reasons. With so many options to choose from, it can be difficult to know if your web host is the best available for your needs.
If you're not only moving your site to a new web host, but you're also changing your URL, there's an additional step. Once the DNS change has been made, you can return to your old server and delete the files and database from the site. It's especially important to do this now, before your website goes live and any errors are made public (and may be more difficult to correct). Keep in mind that while your DNS settings change, your website is likely to experience a few hours of inactivity.