"Wir wollen auf Deutsch lesen."
There's a Duolingo course for that ;)
Dann ist das hier aber nicht der richtige Kurs :^)
Yes, we can...
To be idiomatic, this should be 'We wish to read German,' not "in German."
If you consider an elided "something" or "it" in the middle, then "in German" isn't wrong. Particularly since there is already a set of exercises trying to teach that "German" = germanice instead of lingua germanica.