We have an interior brick wall that we want for seal to stop brick dust.
What is the best way to do this or what product do I need to use?
Depends on the look you want. If you want to preserve the natural brick use a clear acrylic sealer. Or you can paint it the color of your choice. Either way, you'll need to clean it well (and let it dry for a while) and follow product application instructions (paint may require a primer) - there are lots of product options available. Acrylic sealer is a nice look.