My 7 phone will not update because it says I do not have enough space on my computer. I have 44 GB left on my computer.
How much storage is used on your iPhone?
I had a similar problem, after I replaced my iPhone 5s with 64GB by an iPhone X with 256GB. The first iPhone backup on my Mac needed 128GB on my Mac, because the iTunes backup included all photos from the iPhone, even with the photos on the iPhone syncing with iCloud Photo library.
Since I did not want to afford more than 100GB for each iPhone backup on my Mac, I switched from iTunes backups to iCloud backups. My Mac has only a 1TB SSD drive, and sacrificing so much storage for iTunes device backups is simply too much. As long as my iPhone had only 64GB of internal storage, I preferred the iTunes backups.
Using iTunes to backup an iPhone has the bonus, that the backup is locally stored and we do not need an internet connection to restore the iPhone. But if you also have an iPhone with 256GB of memory, it may not be feasible to free so much storage on your Mac, that you can make an iTunes backup. If your computer is a desktop computer it is no hardship to move most of your data to external drives, but on a laptop you may want to use the internal storage for the documents ad data you want to be accessible at all times, without external drives connected and not for iOS backups.