We all start somewhere. Best to get your priorities straight though. The basics are easy to get down. Have fun, prepare appropriately, check forecasts, test your stuff in your backyard, make sure you know how to set up whatever shelter you have in the rain, always do a gear check before you head into the field and start small. Always leave iteneraries behind with people you can trust. Go with other people at first, it's more fun that way plus you learn a lot from each others stories. Once you get dialed in then try solo trips if you desire the solitude.
Shaving weight is more of a way of thinking. It comes with experience and is a way of thinking "do I really need that?" or "is there something lighter or more compact?" The fact your on this web site means you've got a good resource right in front of you. The BPL book is a very good one, but it does assume you already know how to take care of yourself as it's focus is solely on lightening your already functional load. I suggest you take a look at the thread "When have you gone too light?" here on the forum. It'll give you the idea of the weak points of going light when you aren't adequately prepared.
The survival stuff walks a thin line between novel, necessary and useless. Also, reading too much into stuff made by the military or survival nuts will make you paranoid that you need 50 lbs of gear or that the goverment is out to get you. If you aren't planning on living off the land and growing a giant beard best to start elsewhere.
Unless you are in berry country eating native plants is a novelty at best but the risk of occasionally mis-identifying an item makes it an unnecessary risk for the possible 100 calories. Even if you get the right ID sometimes you'll end up with the runs or major gas regardless since it's food that you are not accustomed to.
In situation of being lost H2O, staying warm (or cool) and getting found is your concern, if you prep appropriately and build your skills your goal is to not be lost long enough to need to foreage to survive. Your body has fat stores for such events.
Things like making tinerballs, using strikers for firemaking and such are an excellent skills to practice but using a firebow for example is a novelty, best to just pack appropriately. Stuff like making a bow and arrow however is frankly useless with modern hiking. It takes considerable time and is just busy work since small game is easier to obtain through other methods and more plentiful. Not to say such skills aren't fun to learn but you've gotta be realistic about which skills you need first.
Also worth noting: a lot of the survival methods are pretty high impact and may take hours of sustained effort to make quality shelters. In CO we are pretty LNT so field practice isn't practical unless it's on private land. Speaking of which totally look up the guidelines on Leave No Trace - some of their hiking info is good for beginners to at least be familiar with.
Efficency comes from practice. The more you keep tweaking your kit the better you get at it. However, the more changes you make in gear the more you fiddle with it.
Navigation: I suggest you start off with one of REI's USGS clinics. They have them several times a month at each Colorado REI. They might point you to an overkill compass but the orienteering information they present is solid. It's even free to boot. It's good for basics. Thankfully here on the front range we've got identifiable peaks for triangulation if you want to play around with the concept. It's suprisingly accurate and not too hard once you get the concept down. They have hiking and backpacking classes too but I haven't seen their content personally. Thankfully the REI's here in colorado do preach going light usually. Their version of going light just happens to be what they stock generally though.
The novelty survival classes are stuff like the cottonwood institute. It's expensive but fun type of stuff. However only 5% of the stuff you learn there is actually field useful stuff but you walk away with more of an attitude that calms the fear of the wilderness. The whole thing there is more of a mental prep anyway. Just like the military pounds into you during boot camp: being lost, pain and discomfort will not kill you - hypothermia, significant injury and significant dehydration will.
Medical training and knowledge is always a useful skill. The more you know about real first aid the less of a med kit you tend to take since you can improvise with what you are already carrying. The exception seems to be practicing professionals. They tend to prepare for treating stuff in the field that most of us would slap a bandage on and worry about once we're back in civilization.
A wilderness first aid class is great if your hard core into it but simply starting with the Red Cross's first aid certifications are a cheap and easy way of getting the basics addressed if you need a refresher or practice on actually using the techniques.