I have a K3 and would appreciate some instruction on how to maximize it's use. Anyone interested?

What kind of photography are you into (or want to get into)? Or, what kind of use do you want to maximize it for?

I ask because I would be a horrible choice to instruct someone on how to shoot sports photos, or travel, or food.

Step #1 for me was to rig up a secure way to have my K3II with me in my vehicle at all times. I have way too many unplanned shots taken with a 20mpx camera phone. All of these would have benefitted from the dynamic range and lenses of a DSLR, particularly when your goal is to print at 8 x 10 or greater.

I'd like some more insight in how to use the features (e/v, LV screen). Bought the camera for candids/ street photography, architecture, and food.

Welcome. This is less a thread for camera advice than it is a thread for pix taken in the DC area, but the first advice I have is read the manual while you have your camera at hand, and do what is written there for each function. Learn how to use the front and rear wheels to control aperture ,shutter ISO, learn them so well that you don't need to think about it. Personally, I do not use LV, I prefer the viewfinder.
Next, read other threads here with photos of things you are interested in, and threads about technique. Look at work of photographers here whose work you like, read the EXIF data and try those settings. Reach out to them and ask their advice. There is no easy way, you have to get out and take a few pictures regularly.
Trial and error, as long as you pay attention to what you are doing, will teach you a lot about where your technique is lacking. shoot a street shot, and architecture shot, a food shot at least once a week, if necessary t every day,and review those three shots and see what you think you lack, then work to fix it. Is composition lacking? Slow down, compose the shot in your mind, then move your position to achieve that compostion. Is it lighting, is it shutter speed? Adjust accordingly. Do not worry about taking only one shot, and having it be perfect. So, RtfM and get out and shoot, if you are in the DC area you have no end of subjects. I look foreard to seeing your pictures.