Is it possible to move a front door?
A front door is just a controlled hole in the wall.  But it is very controlled. You are right to think that there are structural issues.  The wall where the door is located has several of its upright structural members (studs) removed. There has to be a horizontal support (header) added to make up for that, and extra vertical supports under that.  The exact size depends on span and what is over the new door area. You may need an architect or engineer to confirm the ability to bear the load above. 

There is also the issue of sealing against weather, both air and water. Flashing, insulation and a variety of seals are needed to keep the outside outside.

Finally, the entry landing has to be appropriate. If above grade, adequate steps or decking is needed.

Since you are asking, it sounds like this is not a do-it-yourself project that would be within your comfort zone. You may want to get a contractor in to give you an estimate.