Bluetooth connection is no problem.
You have to use the musiccast app (iOS or Android).
PC: there is a USB port and this should be possible.
Inputs: there is only one set of cinch (analogue) inputs. You will have to choose between the cassette/cd player and the phono. Judging by the presence of a preamplifier on your turntable, it should be possible to connect the latter, but this needs to be checked.
Cd: ideally you should have an optical output on your player to use the optical input of the wxc-50, but this does not seem to be the case on your TEAC.
The main quality of this device is Multiroom musiccasting and network playback from sites like qobuz or Spotify.
It is very musical.
As far as active speakers are concerned, the unit is intended for connection to an amp or musiccast active speakers. If you have another brand, it depends on their connections.
Instructions for the wxc-50 are easy to find online.