Internal opening is closed.It may be blocked with crusts..your language dead dried cells..or it may be due to immature or pre- formed tract
Whatever fluid getting is due to infection set in tract..
Just try to avoid wetness at that area
Next Steps
As of now no surgery suggested
Maintain personal hygiene..
if pain or discharge present..get examined periodically like once per month..
Health Tips
As of now personal hygiene is enough..
But periodically examination better to have