Yakuza 0 is my recommended starting point for anyone new to the series and remains one of my favorites of the franchise. This game has a gripping main story, lots of substories, and lots of fun minigames to master.
This guide will cover all main story chapters, substories, and minigames. Throughout the guide are several Notion databases that provide information on items and completion requirements. To make the most of those, I recommend duplicating this guide into your personal Notion so that you are able to make use of the interactive checkboxes located in to-do lists and databases. This will make things easier for you to track as you play.