Need your help on these complete deck posts

Hello friends. Not a collector, but the father of one. Love these posts showing a full collection ny so. Has been collecting since 2015. We have piles of boxes. Problem is, i, as an openly admitted noob, have no clue what card comes from what set.

With my sons HS graduation upcoming, i would LOVE to create something like the posts i see here, capturing a fulll set.

Where, and how, do i start? I have thousands of cards i can use. But they have no rhyme or reason.

Grateful for any insight in making a memorable goft for my boy.