MyNoise is an amazing ambience website for whatever ambience you want! It has an advanced-enough generator, and gives you enough control and noises if you are a free user. By just donating 5$, you can not only support a big passion project, and get yourself a lifetime paid version of MyNoise! (Although please do donate more than 5$ if you can) - https://mynoise.net/
To train your PFC (prefrontal cortex) is to train your lucidity. N-back is an amazing game to improve your passive and active short-term memory! The game is currently swimming in research limbo whether if it improves your brain or not (most research is leaning on it does right now), but anecdotes and certain "rules of thumb" of me tells me that it does work well! It is a game that can induce lucidity. I am currently experimenting and playing this game, and will do a more in-depth documentation (follow c/braintraining for that pls) - https://brainworkshop.sourceforge.net/
https://ld4all.com/ - THE lucid dreaming community. Do I say more?
All-Day Awareness is a very hard to achieve, but a very rewarding "Always Lucid" tech that allows you to see constant LDs while practicing a near-constant "meditation" of sorts by paying attention to regular actions like walking, conversations, what not like if you are meditating. You need a very good PFC for this, obviously. https://www.thelucidguide.com/Techniques/All-Day-Awareness-(ADA) https://www.dreamviews.com/induction-techniques/113253-all-day-awareness-dild-tutorial-kingyoshi.html