For sure be on the lookout for apps that you already know and trust first, but I would try searching first in Gnome Software, which connects to Fedora’s repos. Those specific builds have been reviewed by the Fedora community and are coming from Fedora infrastructure. With downloading apps directly from websites (1) you may run into availability problems and (2) you’re trust that the website itself hasn’t be compromised. Is it unlikely that Discord’s website will send you malware? Highly. But the software center would be a more secure way of getting those apps.
Even if you do want to go straight to the source for some apps, I would at least use the software center for apps you’re not as familiar with. For example, if you want to do video editing and need a substitute for Adobe Premiere, don’t just download an alternative from any old site. Go with the builds that Fedora provides because those have been vetted.