If you find difficulty in smiling that means you are not enjoying your life.
Does the sentence contain any errors?
Thanks.
In my opinion this would be better:
If you find difficult smiling, that means/it means you are enjoying your life.
''If you find smiling difficult'' can also be said.
OR
''If you face difficulty in smiling'' would also be OK.
Anyways I would prefer the very first one
ps I'm not a teacher!