You really are getting way ahead of yourself.
If you've only had 3 lessons, you should just about be able to fly straight and level, and possibly climb and descend accurately. Anything else at this stage is a bonus.
Landing the aircraft is actually lesson 13, although you may well be able to land an aircraft before that. When you actually come to lessons 12 and 13, you'll have a few more hours under your belt and will probably fly somewhere in the region of 30 landings for practice (3 hours or so at around 10 landings per hour), so any problems will soon be fixed.
As for navigation, that doesn't even start until lesson 18. By then, you'll have around 20 hours, have flown flights into double figures and generally be more familiar with the local training area.
Raise the concerns you have with your instructor and he will help you to see what is relevant now and what you have to put out of your mind and focus on later.