If something is near then it is a short distance away. It can talk about physical, time and relationship distances.
If something is nearby then it is a very short distance away. The distance is less than something that is near. It can only talk about physical distance.
- Our new house is near the school.
We are nearby the deadline for job applications.
(nearby can only talk about physical distance)
We are near the deadline for job applications.- There is a park nearby where we can walk the dog.
- We need to find a petrol station nearby because we are low on fuel.