You can live a totally normal life! You might have to accept certain limitations though, such as not being able to do certain sports or taking a lift rather than going up the stairs. Please do not try to continue these things if they are really painful cos it'll just make you sad, however don't let pain stop you from doing the things you want to do in life, just, adapt them slightly to make them easier for you to complete
What kind of arthritis and how does it affect you currently?
I have hEDS and unfortunately sometimes I do have to accept my limitations. But I still manage to live a relatively normal life for now at least.