How to check Pokemon GBA Carts

Hi guys (and gals)! I recently got into this Pokemon thing again, it was ages ago when i played my last pokemon game (RED, for gameboy) then decided to buy the Sword / Shield bundle. Days passed, I have a Living DEX!!! After catching them all, I want to collect the main series games starting from Red and Blue upto Sword and Shield. Not only the carts are expensive, there are also lots fake copies, so here, check out these pictures for reference