Do I need something more than Redis?

I am new to Easy Engine and to setting up LEMP stacks. I am confused about the different types of cache: page cache, object cache, nginx cache (is that perhaps a page cache?).

I installed Redis cache, do I need to install another cache as well?

Do I need to adjust the settings for the cache in any way? I have 8 GB of RAM in my VPS, using at most 2 GB at the moment