Is the only sound for that video the propeller noise.
If so, import that video to Video Track 1/Audio Track 1, right click the file there, select Delete Audio.
Then import your music file and drag it to the Soundtrack or Audio Track 1 directly under the video on
Video Track 1.
Please let us know if the above is what you sought.
Thanks for the assist. That is what I needed.
Thanks for the follow up that the replacement of audio is what you sought and not the removal of unwanted noise from within the video.
Best wishes with your projects. Any questions or need clarification, please do not hesitate to ask.