Chosen Solution

just got my MacBook Pro 13" Retina Display Mid 2014, 8 gb, can I upgrade it to 16 and how?

Sadly, no. Your system has soldered in RAM. If you really think 8GB won’t work for you I would see if I could return it and get the 16GB model.

Are the memory chips soldered onto the main logic board? If so, can the memory be upgraded by swapping out the 8gb logic board for one with 16gb on it? If so, is it cost effective to do that?