Yes. Without decompression a flac file contains just pseudo-random data. A media player requires an ordered stream of PCM stereo audio samples in order for them to be converted to analogue audio via a DAC chip. Therefore, we implement 'codecs' (Code-Decode) to handle the decoding of the flac data to the ordered stream of PCM samples we require to be fed to the DAC.
There are various different types of codec, some use 'lossless' compression techniques, some us 'lossy' compression techniques.
A 'lossless' codec will retrieve an identical sample stream from coded data. A 'lossy' codec will retrieve an 'audibly similar' sample stream from it's coded data.
Codecs are specific. You can't decode one data stream from Codec A with a different codec format.
Therefore, the answer to your question is - yes - it would be exactly like listening to the original uncompressed song.
Remember that media players don't all support all codec types. Check with your media player first before using a particular codec to encode your music.