I have been looking for information like this for a while. Thank you! Follow up, does the IMEI number get broadcast when you connect, or is it a searchable bit

I have been looking for information like this for a while. Thank you! Follow up, does the IMEI number get broadcast when you connect, or is it a searchable bit of information accessible by apps, et al? Im wondering how anonymous you can be if youre making all the right privacy moves, but your phone is still essentially giving you up because your IMEI number is traceable back to you.