She’ll is not available on free hosting. Please upgrade to a VPS or premium if you need it.
Never heard of this, but I don’t think it is disabled. You may have to install some library to use it, though. Note: This looks like a server-side cache, which is probably not supported here.
Redis is not enabled, so it is not supported. If you need it, I think premium may have it, but you’ll have to raise a support ticket to find out.
We don’t have Opcache on our servers. I’m not sure how effective Opcache is with how we run PHP, but seeing how the servers run a large number of websites with very little traffic each, I can’t imagine cache hit rates would be any good.
Redis and opcache are useful on high traffic and/or high complexity sites. And sites like that aren’t going to run well on free hosting anyways.