Jameson Loop website has a lot of resources about bitcoin and lightning network.

You can start in there.

Mailing lists are also a good source of information.

https://lists.linuxfoundation.org/pipermail/lightning-dev/ https://lists.ozlabs.org/pipermail/c-lightning/

The Git repo of each implementations is also useful. Besides the help with any issue you have with the software. You have links to sources of information. Like:

Core Lightning

"Any help testing the implementation, reporting bugs, or helping with outstanding issues is very welcome. Don't hesitate to reach out to us on IRC at #lightning-dev @ libera.chat, #c-lightning @ libera.chat, or on the implementation-specific mailing list c-lightning@lists.ozlabs.org, or on the Lightning Network-wide mailing list lightning-dev@lists.linuxfoundation.org, or on Discord core-lightning, or on Telegram Core Lightning."

LND

" Finally, we also have an active Slack where protocol developers, application developers, testers and users gather to discuss various aspects of lnd and also Lightning in general."

" #lnd @ irc.libera.chat"

Don't forget to check the websites, twitter and telegram too.

https://blockstream.com/lightning/ https://lightning.network/

These are only two of the LN implementations. In Lopp website you can find the other ones.

But in the end the best way to learn is install the software and use it.