Here is a quick video on how to upgrade a SSD on a MacBook Pro from 2012 – 2015.
Tools: 1 x T5 Torx Screwdriver.
1 x P5 Pentalobe Screwdriver
1 x Anti Static Wristband Wrist Strap Band ESD Discharge
1 x Anti Static Mat
1 x SSD M.2 NVME (check before you buy it does work with the model)
Time: 10-20 minutes to install around 1 hour to install the Operating System.
Skill: Easy