Ah! I see what the problem is. Heh. Ok, my bad. Please bear with me, because I have to lay some foundation to explain.
Most (?) Linux distributions ("distros") have GUI package installation and update managers. (There are also command-line analogues for the GUIs. This is, after all, Linux
) There are default repositories ("repos") that go along with them. Not all packages from all sources are included in all repos for all distros. Particularly packages that are forks from major packages.
(Sidebar: Debian and Debian-derived Linux' [Debian, Ubuntu, Mint] use the "dpkg" [Debian package] package management system. Red Hat and Red Hat-derived Linux' [Red Hat, CentOS, Fedora] use the RPM [Redhat Package Manager] package management system. Ubuntu and Linux' derived from it, such as Mint [yes: Debian begat Ubuntu begat Mint, you could say] add another package management layer atop dpkg, call "apt". )
Brave is kind of a fork of Chrome. (It uses the Chrome rendering engine.)
Often, packages that aren't included in a distro's default repros have alternative package sources that can be manually added to a distribution's package management system. In Debian-derived systems these are called "PPA"s (Personal Package Archives).
*whew*
All that was to explain that the command-line part of what you are seeing in "installing" Brave isn't to install Brave, per se, but to add a Brave PPA to your distro's list of repositories. After that's done you can use either a command-line package management tool or the package management GUI to install or remove the package. After that's done, updates come via the same mechanisms as updates for all other packages.
It's
never going to be where MS-Windows and MacOS are, because Linux is all about choice. Think about it: Can you see MS-Win allowing one to add alternative/additional package sources to their built-in package management system? Does MacOS allow one to do that?
I don't know what went on with what you were doing. The only time a new Linux install took me more than, literally, minutes to get started was when I built the machine I'm currently using and wanted to use the Linux kernel's built-in RAID. That was a bit tricky because I wanted to boot off the same SSDs, and you can't boot off a Linux kernel RAID instance, because it doesn't exist at boot time.
I've no idea what a "Magic Mouse" is, but, yeah: If it's something non-standard-ish, support may be tricky, or even lacking entirely. E.g.: the keyboard I'm currently using uses a different method for communicating caps lock back to the keyboard to light the keyboard indicator, and my Linux kernel is too old to support it. So I have no caps lock indicator.