This is what I've done the past couple weeks and it's going pretty well:
Start with plain Emacs. Print/write out the popular cheatsheets. Just make sure you know how to exit, access the documentation, and move around the windows/frames/buffers. Get Melpa & install some packages. Play with the config, adding keybindings, figure out hooks and so on. Copy some elisp functions from dotfiles on Github. Spam the documentation command on everything. Get frustrated with how much tinkering you need to do to get the crazy setups you've seen on blogposts. Stay motivated by consuming more content about custom setups. Discover the magic of magit and parinfer and dired. Look up some of the org-mode/PIM heroes on github, usernames: novoid, alphapapa, karlicoss
Install Doom. Tinker with it a bit. Take notes of your learning in an org file. Tinker some more. Go back to plain emacs for a bit. Then try spacemacs. Go straight back to Doom because it's faster and you now understand enough about emacs to be scared of spacemacs' layers.
Below are some links to help you along the way.
http://ergoemacs.org/emacs/blog.html
https://sachachua.com/blog/
https://www.gnu.org/software/emacs/refcards/pdf/refcard.pdf
https://orgmode.org/worg/orgcard.html
https://cestlaz.github.io/stories/emacs/
https://www.youtube.com/watch?v=0g9BcZvQbXU
https://zaiste.net/doomcasts/