Welcome Giorgio!
IF you think you are old at 36, what does that make us fifty somethings?

Gary Cassara learned to ski at 36 and is wonderful skier, smooth as silk via PMTS. I also learned at age 36 and wished I had had the knowledge to learn via PMTS from the get go. The wasted money I have spent thru the years on go-nowhere lessons and bad equipment.
Your initial instinct to get well fitting boots is a smart one. I suggest you GO WITH IT!
There are PMTS instructors (I think?) in europe, there is a camp led by H.H. to Hintertux each spring.
I suggest you do some research thru Realskiers, which can lead you to Harb camps and others that are close in method to PMTS. The Deslauriers, Lito Tejada-Flores all seem to come from a similar direct to parallel ski background and avoid teaching the, hard to lose, snow-plow.
Getting some good starting lessons can make the difference between having the ability to move ahead smoothly in skill level vs a set of skills that will keep you from being able to improve, just survival on the beginner hill.
Let us know what you decide on.