I upgraded safari on my imac 2013 and the latest version of safari is not supported...How do I find the right version of Safari to run?? Currently unable to connect to the internet

You should know that Safari normally can not be individually installed. It is installed as part of the Mac's operating system. When the OS is upgraded, Safari will often be upgraded as well. I t would be useful if you were to explain what you mean when you say that Safari is "a version I can not support. That is not useful information which we can respond to. If you wish to have a different version of Safari installed, then you will get that by upgrading your operating system, if your computer is capable of being upgraded. You can also try using another browser such as Firefox or Chrome to see if it suits your needs.