Try playing the flac file using the DVD player. Most modern dvd players are equipped with the universal firmware, it includes a large number of codecs that support most of the existing audio and video files.
Note the flac file on CD or USB thumb drive (if your dvd player has a usb connector). If the dvd player is not connected speaker system, i.e. it plays the sound only through the TV, it makes sense to use usb to connect it to the computer (if connected to the computer speakers, or speakers that reproduce sound clearly better than the internal TV speakers).
Download and install to your personal computer program KMPlayer. It is a universal media player that can play flac. Select advanced installation, expand the list of codecs. Some of them are marked by default. FLAC, unfortunately, not among them. Find it in the list, select a tick opposite it and complete the installation of the player.
Run the player, load the flac files in the playlist and enjoy the original sound. Note that for this you will need a good sound system or at least good headphones. The fact is that the records of this format cover an enormous spectrum of frequencies, which greatly have converted to a different format records. Accordingly, to transfer such spectrum need quality equipment. If you don't have, it makes no sense to play such files because the difference between them and regular MP3, you still will not feel it.
Convert flac to MP3. For this you need the program Format Factory or any other program with similar capabilities. To kind of keep the sound quality of the recording, when converting set the highest sampling rate. The MP3 file in this case will "weigh" much more, but sound much better.