How do I seal the gaps on my front door?
Similarly one may ask, how do I seal the gap under my front door?
If you have a large gap beneath the door, use a wrap-around door sweep. They have long adjustable sides that can be moved up and down along the width of the door. When the bottom of the sweep fills in the door gap, drill pilot holes through the sides and screw it down. Put in a door threshold.
Similarly, it is asked, how do you cover gaps in a door?
To keep insects from crawling under your door, install a sturdy steel or aluminum threshold under the door. For even better protection, combine this with a door sweep. A sweep is a cheap device that can be found at most hardware stores, and helps to cover the gap between a threshold and the door bottom.
If the gap is less than 1/2 inch wide, you can fill it with acrylic latex caulk. If it's wider than that, caulk won't bind well, and you should use polyurethane foam instead. Use the least dense foam you can find so that the connection between the jamb and the framing remains flexible.