wildcard redirects only available for enterprise plans

To perform wildcard redirects, page rules must be used. For page rules to work a proxied DNS entry must be configured such that the traffic goes through cloudflare. Wild card DNS entries cannot be proxied in Free, Pro and Business plans.

caching html or audio files

By default Cloudflare does not cache html or audio files. To cache static html or audio you need to use a page rule to set the Cache Level to Cache Everything.