Here are some things that I have personally gone through in my Bitcoin dev learning journey
- nostr:nprofile1qqsd6j6yks9vne0us4ksdp7pqa38ucf94le4per0xnfzh23xrg2njgsua2cgl (bitshala.org) cohorts, specially the Mastering Bitcoin cohort
- Books: Mastering Bitcoin, Programming Bitcoin, Bitcoin Dev Philosophy
- The BOSS program by Chaincode (couldn't keep up because it needed too much of my time)
Also, if you want, get him started with some nostr stuff. Nostr dev is much more fun and easy to grasp. The NostrDevs playlist by PlebLabs on YouTube is a good way to learn nostr if he prefers learning by watching stuff instead reading