If you do not have any type of gastro issues, then you can just swallow the capsules but it is best done with some food (meal) that has fats in it. This does help Vitamin D absorb.
If you have gastro issues and swallowing vitamin d does not raise levels because it does not absorb due to the gastro issues, then there are companies that do make oral sprays which can be very effective when used.
Let me know if you have any more questions!