tell me the how it works validation on lookup field

If I understand correctly, your second object has a lookup field to your first object, and you would like to auto-populate qualification and experience fields on the second object to match those of the first object.

1. Create a new field of Formula type on the second object,
2. Make the return ype the same as the data type on the correspinding field on the first object,
3. Then click on Insert Field,
4. Select the second object (the one you're adding the field to),
5. Select the first object (the one that has the field you wish to reference from)
6. Select the field you wish to reference from.
7. Add the field to the formula
8. Click next and save the field.

Your field will automaticaly populate the value from the matched field on the lookup object.