adjust tempo of whole track to follow songtempo?

Hi,
I am coming from Ableton and using Audio is extremely comfortable there.
I got a mpc one and wanted to make a basspractice programm for me with a couple of songs I am practising.
Unfortunately I don't really understand how to tell the mpc where is position 1 of the song to start the metronome there as well as how to set the root tempo of the song and link the tempo to the songtempo that once set if will follow. I suppose there isn't any way to set markers along the track to keep the songtempo nice and sync? Especially on older stuff the tempo changes quite a bit.
Thanks for helping

You can set the bpm in your sequence for each sequence individually, or set it all the same globally if you switch on "global" beneath the bpm value.
In song mode, the bpm of each sequence is shown ( but not used) even if global is on.
To change the metronome settings click on the metronome icon in the top of the screen.

Not sure if this answers any of your questions.