Capp it will be complicated, if not impossible, for you to work with Flarum if your internet provider is blocking access to the Flarum source code, documentation or community.
I suggest you use an alternate internet connection (mobile data for example?), a VPN, or contact your ISP or system administrator to get the Flarum domains unblocked.
Flarum 2.x is still in development and should not be used in production yet. If you want to try it out on your own computer, you can find the instructions here https://discuss.flarum.org/d/32901-staff-diary-v20-cycle/293