To add a few more resources to those already provided above, with an eye more toward language learning than character memorization:
- I’ve found the Chinese Language subreddit very useful for resources, community, and advice.
- +1 for Pleco dictionary and Heisig resources.
- The Alex Mullen video linked above is based on the Marilyn Method of memorizing characters.
- The team at Mandarin Blueprint have taken this method and developed an entire program around it.
- Hello Chinese is a great introductory learning app.
- If you’d like some more context about natural language acquisition, Stephen Krashen’s work on second language acquisition and comprehensible input is a good place to start.
- there is a 中文 forum here on Art of Memory that may be useful depending on your comfort level with the language.