honestly? just start drawing from life every single day. then do some referenced imaginative drawing, e.g; redraw the subject of your life drawings from a few different angles/with different simple lighting setups from your head, try to replicate the rendering style of an artist or painting that you like.
supplement this study with ONE anatomy resource and ONE perspective resource and maybe one dynamic drawing resource [scott robertson's how to draw, peter han drawing courses]
if you are going to invest money into anything, maybe buy a nice plaster cast, an ecorche figure and a simple lighting setup. try to find figure drawing sessions in your area that you can attend. as you become comfortable with drawing simple indoor subjects, start doing some plein air studies as well.
imo pretty much all the anatomy and perspective books are more or less equal, they are all using different methods to get to the same place, so just look at some pictures and choose the style that makes the most sense to you. personally i like zarins and was very impressed by scott eaton's courses. the most important thing is to simply draw as much as possible even if your output is utter garbage [and no matter how devastating producing garbage is to your ego], no book and no amount of money can do that part for you. similar to language acquisition, the most effective way to build drawing skills in a short amount of time is through pure immersion; turning drawing, like speaking into a natural extension of your everyday life. find ways to incorporate your life into drawing and you will get good.
with that said, these are the resources that helped me out the most in the beginning, plus a few that i wish i had read much earlier
http://www.huevaluechroma.com
https://imgur.com/gallery/Wia19
Alla Prima: Everything I Know about Painting by Richard Schmid
Graphic LA by Robh Ruppel
How to See Color and Paint It by Arthur Stern
Rendering in pen and ink by Arthur Leighton Guptill
https://www.heavypaint.com