Redis and Internal Page Cache?
The Drupal modules decide what to cache (and for how long etc), Redis is just where the cached data is stored. 

Having both/all enabled is not inherently redundant (though as 4k4 noted in the comments, there's a theoretical chance that one cache will improve speed so much that it renders the other redundant in terms of further speed improvements).

Enabling the lot will probably be common practice, and if not with Redis as the storage backend then Memcache, etc.