If you did web development before, just try to use phoenix and write a route, then something with db calls, read docs and so on. Get any elixir book if you like learning from books.

I also did the whole "learn Erlang for greater good" like 5 years ago. It is much easier to understand elixir if you know Erlang, at least to the basic level, as in the end, it is just Erlang.