Have not done the Terms and Conditions thing in a while, but sometimes with these things you have to scroll all the way to the bottom of the screen to make look like you actually read those Terms.  Then the button to accept works.

The other solution - if you have definitely scrolled right to the bottom - and if you are using an iPhone, is to go on the phone to Settings - Display & Brightness - Display Zoom, and set to Default. If that is already default, then in the same part of the Settings go to Text Size and reduce this size temporarily.

This should allow you to Accept the Ts&Cs.