Is discord a good file host?

In some cases, Discord will work file with hosting some files such as zips to share and images but note that Discord is not encrypted and they can see everything you send, while also logging everything. Do not host sensitive information or anything illegal. Edit: I forgot to mention that Discord is not viable for long-term hosting files.

MEGA is another good alternative, while it has low base storage you can get some extra storage by downloading the app, inviting users, and some other ones.

You honestly won't get anything incredible for free, and if it is free you will always pay somehow. I suggest setting up your own server with Nextcloud or an open-source file host. You can easily do this with even a spare computer or laptop.