Adding beats and measures to existing mp3?

I am new to Audacity and I just realized something that would help me immensely. I just have no idea how to do it. I drop in an existing .mp3 file. That works fine. I would then love to be able to pull out beats 1-4 of measure 10 for example. Right now, I have to listen to it and try to pick that section out of a “stream” of data. Very tough. Is there a way to add counts and measures to an existing song? Is the software smart enough to figure that out? (I really have no idea) Then, can I select “blocks” of measures to work with? This would be incredible if I could do this.

Thanks,
Dave

It’s quite difficult for a computer to accurately detect beats unless the beats are very strong. In the Analyze menu is “Beat Finder” that attempts to label the beats http://manual.audacityteam.org/o/man/beat_finder.html If the music has strong beats this might work.