It should ask you to update automatically with a notification-did you not get that?

It should ask you to update automatically with a notification-did you not get that?

Sure if the OP was using Windows, macOS or the Linux Firefox version from Mozilla.

how do i download the latest firefox

You UserAgent appears to be Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:83.0) Gecko/20100101 Firefox/83.0

So either you have not been doing Firefox package updates in your package manager on Ubuntu (or a flavour of Ubuntu) or the likely case due to how old Firefox 83.0 is (released November 17, 2020), you likely have a version of Ubuntu that is old and eol with no more package updates including Firefox packages.

I do not know Ubuntu well enough to know if there is a repository you can add to get more current Firefox packages for your Linux distro without you updating your system to a more current supported version of Ubuntu.

The other option is to use the Firefox tarball from Mozilla as it will get internal updates from Mozilla. Where ever you put the Firefox folder, it needs to have read/write permissions for the user account on Linux in order to get updates from Mozilla installed. An easy way is to put the Firefox folder in /Home if you are the only user. You can find Firefox icons to use with the shortcuts/launcher in the firefox/browser/chrome/icons/default/ folder. You run the firefox script or firefox-bin to start Firefox.

https://www.mozilla.orgfirefox/all/desktop-release/linux64/ https://support.mozilla.org/en-US/kb/install-firefox-linux