Congratulations on starting a new business adventure!

Here are a few things that come to mind:

1. Know the legal framework aka get info on copyrighting
2. Test eBay as its a great marketplace for memorabilia
3. Test live shopping on TikTok and Insta
4. Connect with local bookstores
5. Go to fairs and exhibitions where people devour your type of books; think Anime conventions for example
6. Connect with local businesses to place a few of your booklets - think exposure, attention, and most importantly, feedback (e.g. flower shops, nail salons, hairdressers, gas stations, car washing - you get the gist)
7. Connect with small business owners who run local gaming events (e.g. they play cards, Remy, Monopoly)

Garbiela, you just started the journey. Don't beat yourself up. You found a monetizable niche and you're doing what you love. First and foremost, build a solid foundation, and learn to master the fundamentals in business.