Q.Maidenhair fern
My maidenhair fern has white dots on the tip of some of the leaves. The clerk said it did not have bugs but I am wondering if there is a scale insect of some sort on the plant and if so, how to treat it.

Mealybug are often found in clusters. Mealybug can be treated with Neem Oil.
Here is a link with more information.
https://www.gardeningknowhow.com/plant-problems/pests/insects/mealybugs-control.htm
I do think you are describing spores on your fern though, so here is a link with more information and some images that will help you determine
if this is what your plants looks like.
https://www.gardeningknowhow.com/plant-problems/pests/insects/mealybugs-control.htm
In the case of spores, you will not need to do any treatment, this is naturally occurring.
https://u.osu.edu/eeob3320/2015/04/19/ferns-part-2/
Here is a link to refresh you on the care requirements.
https://www.gardeningknowhow.com/ornamental/foliage/maidenhair-fern/maidenhair-fern-care.htm