The AppImage is just a squashfs container. From your scropt you can mount it and run the executable or even extract it once and then run the executable from the script. Mounting is easier if the appimage updates itself. More information
It has to be a credit card as under 18s can get debit card.
Not to mention that removing that field won’t make you adult. Without it you can either not go to certain websites or download applications from stores like Flathub or the system assumes that you are a toddler and only let you visit baby tv.
But without the addictive design the users don’t spend enough time to see all the ads and tracking required to reach the target growth. Somebody think of the shareholders /s