Changing a Push Button Toilet to Use a Handle?

I have a toilet that has a push button on the side for flushing. I would like to make the push button flush into a handle flush (I have very little strength in my hands and fingers due to a neurological condition). It sounds simple but the mechanisms are very different. Has anyone had this problem before? How did you fix the problem ? Did you do it yourself or called a plumber? If you made the change yourself was it difficult? I am open to any suggestions or onions. Thanks in advance.