Can't Download New MAC Operating System

Trying to download the new mac operating system to my Macbook pro as this is apparently needed to remove my phone from disabled mode, without luck trying to get my phone working again.(I've been working with Mac support for nearly a week (unbelievably frustrating process since I can't just go to the store & they never have appts in my area now with their crazy limited Covid hours). The most recent tech support person told me the many failed attempts following the steps a Mac supervisor gave me, failed bc my operating system is not up to date.

So I have been trying to download the new OS all day long without any luck. I can't find strong enough internet any where. I have been on decent internet at the college, but it still takes 7-8 hours & somehow without fail, it runs into some random error - or the internet briefly drops out due to storms in the area (6.5 hours into the process). Unfortunately, for some god forsaken reason, EVERYtime the internet drops or gets too weak- even momentarily, it looses the 6+ hours of downloading it has already done *& has to start from the beginning AGAIN! This is COMPLETELY insane. What on earth? THe rep never mentioned it was a 7-8 hour process (on my internet it said 12 hours)... and said she'd call back in an hour to make sure it worked... of course it was no where near done & was supposed to call back later, but didn't.

I have now been working on this ALL DAY long & most of the night & bc of this ridiculously poorly designed glitch, I have accomplished NOTHING except to waste ANOTHER entire day AND NIGHT ON failed suggestions.

Surely there is a way to resume the download of an enormous program like this 12.41 gigs without having to start again from the beginning any & every time the internet slows down or drops out???? If not, why on earth would Apple not offer a version of the download for people without access to lightning speed internet, that can be downloaded in segments... so if one failed, you would only loose a gig or 2, instead of 9 or 10 gigs out of a 12.41 gig program that is IMPOSSIBLE To finish for anyone without an ethernet cable or amazingly fast & expensive internet???? Certainly there has to be a better way- how come I can't find any work around for this... I am so unbelievably frustrated at this point- between my glitchy phone with constant problems that finally became disabled whenI tried to restart it after clearing a bunch of pictures (did not EVER enter the passcode incorrectly- when it came back on-it was suddenly-without any prior warning -in disabled mode ... and both of our computers- which due to imperfect internet, are incapable of completing this whole ridiculously large download without a minor drop in service that requires us to start over on the whole day long impossible project again!!!

This is INSANITY.... also, if it takes hours longer than you expect & you need to move from where you are, it should be possible to pause the download & then restart it where you left off when you get to the next internet connection- not another impossible chance to start from scratch YET AGAIN!