WEB SITES

You need to use a current third party web browser. All of the regular third party browsers no longer support such an old OS, in fact, they are now only supporting the last three versions of macOS which Apple still fully supports. At this time they are Sonoma, Ventura, and Monterey.

You may be able to use Firefox ESR (I forget the version number) and possibly Vivaldi 6.2 (must be using Chrome v117 engine which is the last version supporting older versions of macOS IIRC). Within the last few weeks I posted on this forum for another user their options with download links to various browsers since it was a bit of work to find the exact versions & their download links. I cannot find that information at this time, but will try to remember to check my other computer.

Keep in mind that if you have any third party 32 bit apps installed, they will no longer work and you may have difficulty uninstalling them once you upgrade to macOS 10.13+. It may be best to see if you can upgrade any 32 bit only apps to 64 bit versions now since it should remove the 32 bit version. However, the current versions of many third party apps may not be compatible with such an old OS, so it may get complicated. If the app doesn't have a 64 bit version, then it would be best to uninstall the app now by following the developer's instructions.

32-bit app compatibility with macOS High Sierra 10.13.4 and later - Apple Support

This well-respected free App can help you look for apps that might need upgrades:

https://www.stclairsoft.com/Go64/index.html