Hiya!
Cartographers Guild (
www.cartographersguild.com_) for RPG map making is particularly nice. Lots of different ways to tackle map making; you could use use a specific program for it (Dunjinni, NBOS Fractal Mapper, or Campaign Cartographer, etc), or you could use a paint program (ArtRagePro, Photoshop, Serif PhotoPlus, Corel Painter, etc)...or, most likely, a combo (Campaign Cartographer for the rough black/white line art and layout, then export as png and import into PhotoPlus). Most of the "pro-looking maps" on Cartographers Guild tend to be combo or 'paint program only' (frequently Photoshop).
Learning to draw anatomy? Hhehe...dude...prepare to be learning for *years*. But, the best way is to grab a package of HB and B2 pencils, a white eraser, a kneaded eraser, and a stack of photocopy paper...then draw stuff. Just draw...stuff. Whatever you feel like...stuff around you, or try and imitate a picture you like, and, yes, even tracing a picture can and does help. Drawing is mostly about training your fine muscle control of your hand and internal 3D imagination. You can also go the digital rout, but you will be investing a lot more cash; you need ample RAM, a decently fast system, and a quality graphics tablet (start small...you may not like drawing on a tablet; Wacom (brand) is the standard and easily worth the price, but for a tighter budget you can pick up a Huion brand one for about half to a third of the price of a similar Wacom).
Depending on if you want to go hard-core realism or if you want to go more comic-book 'as long as it looks cool', you can try and find a couple of books I've used. Look for "Hogarth ; Dynamic Anatomy", "Bridgemans Complete Guide to Drawing from Life", and "Figure Drawing: Design and Invention". Read them. Also, you may want to sign up for a life-drawing class/course. Many free'ish life drawing "groups" (like, $20 for a few months of weekly 2 to 3 hour sessions using actual live models) can be found by just looking in your papers classified ads.
If you want more comic-book style, there is simply nothing better than Stan Lee and John Buscema's "How to Draw Comics the Marvel Way". Get one. Hell, get one even if you want to go the more realistic route. Easy to understand, entertaining to read, clean, big picture examples, and words of wisdom from two of the most iconic names in comic books.
Lastly, buy art books. "Coffee Table Books" as they are usually called; you know the ones...heavy, expensive, high-quality colour art books that are typically titled "The Art of [insert artist/game/movie name]". Obviously you will want Frank Frazetta, duh, but others like Brom, diTerlizzi, etc might fit the bill. Basically, any artists you like.
Oh, and don't discount spending hours scouring the net and youtube for tips. One guy on YouTube that I quite enjoy listening to is a guy called "Borodante" (here,
https://www.youtube.com/user/dante88s ). He has a quirky personality, and really thinks through his art...and he describes what he's thinking and why. A plethora of digital painting tips have made their way into my brain.
Oh, ONE more thing.

Start a "Reference" folder. If you search around enough for tutorials you will find quite a few 3D and 2D artists that will espouse the virtues of having your own personal "Reference Library". It will get big. VERY VERY big... I have one specifically dedicated to female form, for example, that is about 3GB in size (when you consider most pics are compressed and between 100k and maybe 2MB...that's a LOT of pictures!). But I have other catagories too..."Rust", "Old Wood", "Water", "Concrete", "Stone", "Space", "SlimeyCriters", "Winged", etc, etc, etc. Get yourself a 'cheap' digital camera...no, not your phone. Get an actual camera. Take it with you whenever you can and take pictures of things you fine interesting or cool...for colour, texture, shape, uniqueness, whatever. To help you organize your pics, there are many programs out there for it. I use one by Serif called "SerifPhotoStack" lately...but there are others. I used to use "ACDSee" waaaay back, but haven't in probably over 4 years or so.
Anyway...yeah...I don't mean to overwhelm you, really, but it takes dedication and commitment to really get better at drawing. For a bit of inspiration, here's a guy (mostly a 3D guy) who uses Blender (a free 3D program), but wanted to get better at drawing, and how he managed to do it, as well as 'tips' from pro artsits:
http://www.blenderguru.com/articles/7-habits-highly-effective-artists-bcon-2016/
^_^
Paul L. Ming