There are two audio types in Godot ( and many other game engines ). Samples and Streams.
Samples
A sample is an uncompressed piece of sound that is loaded into memory.
Samples take up more memory but a great deal less processing power.
In Godot you create samples by importing them as WAV files.
Streams
Streams on the other hand are instead compressed audio files (think MP3), often much longer in duration.
These you simply copy into your project, Godot supports MPC and Ogg Vorbis formats.
Generally samples are used for in game quick sound effects, while streams are used for background music. There is a pretty good chance your audio isn’t in WAV, Ogg or MPC format.
If it isn’t, I highly recommend the free program Audacity for converting between formats.
For more of this and HOW to incorporate Samples and Streams....
