Not sure that a dedicated server is necessarily the best option for this.
I agree that streaming from home won't get you very far unless you have a tiny number of simultaneous users, but I'd consider a service
like this one - for example
Google will help you find many other similar companies too - I should stress that I know absolutely nothing about the one linked to, and simply provide it as an example of what's available (not certain exactly how suitable this particular one would be for your needs either).
My point is that you can find various specialist services that are made for this type of thing; you wouldn't need to spend as much money, and wouldn't need to go to the same lengths/frustrations of trying to configure it yourself.
Depending on who you go with, you may also find that the quality of service (for your users/viewers) is way higher because some streaming providers will use a distributed network which ensures better connectivity to a global audience.