Who do I reinstall after SSD replace
Mac Pro Retina15” 2013 256g. Attempted to upgrade to High Seirra and my computer died. Tried everything black screen. I did get recovery to come up a few times ran repair but did’t find or fix anything. Purchased new SSD 480 g , took old one out and put in a catty and transferred my files to an external storage via another Mac air. Now how do I reinstall Operating system on my New SSD? Can I run some sort of backup/reinaller by accessing my old SSD which is connected to my Mac air in the catty? Any help is appreciated. Sorry if in wrong place working off iPhone.