One game like Kingdom Hearts story is Final Fantasy. It has a rich and complex narrative with elements of fantasy, magic, and a battle against dark forces. The characters are well - developed, and the world - building is extensive, much like in Kingdom Hearts.
The Legend of Zelda series is a great example. Games like Breath of the Wild have an immersive story where you, as Link, are on a quest to save Hyrule. The open - world exploration and the way the story unfolds as you discover more about the land and its history is somewhat similar to Kingdom Hearts.
The order is: Kingdom Hearts: Birth by Sleep, Kingdom Hearts, Kingdom Hearts: Chain of Memories, Kingdom Hearts II, Kingdom Hearts 3D: Dream Drop Distance, Kingdom Hearts III. But this can be a bit complex as there are also other titles like Kingdom Hearts: Re:coded that fit into the overall story timeline in different ways.
The order is Kingdom Hearts: Birth by Sleep, Kingdom Hearts, Kingdom Hearts: Chain of Memories, Kingdom Hearts II, Kingdom Hearts 358/2 Days, Kingdom Hearts: Coded, Kingdom Hearts: Dream Drop Distance, Kingdom Hearts III, and Kingdom Hearts: Melody of Memory.
Kingdom Hearts: Birth by Sleep, Kingdom Hearts, Kingdom Hearts: Chain of Memories, Kingdom Hearts II, Kingdom Hearts 358/2 Days (although its story is intertwined with the others), Kingdom Hearts Re:coded, Kingdom Hearts: Dream Drop Distance, Kingdom Hearts 0.2: Birth by Sleep -A Fragmentary Passage-, Kingdom Hearts III.
In order, we start with 'Kingdom Hearts'. The story begins in Destiny Islands, where Sora's world is shattered by the Heartless. He then travels through various Disney - themed worlds, fighting enemies and making allies. 'Kingdom Hearts: Chain of Memories' is set in Castle Oblivion and is crucial for understanding Sora's past and the concept of memories. 'Kingdom Hearts II' sees Sora's return, stronger and with more determination to save the worlds and his friends from the forces of darkness.
Well, 'Kingdom Hearts 1' is the foundation. Without it, you won't understand the whole concept of the Heartless, Keyblades, etc. Then 'Kingdom Hearts: Chain of Memories' which is important for the transition of the story. 'Kingdom Hearts 2' continues the main narrative. Also, 'Kingdom Hearts: Birth by Sleep' is quite significant as it reveals a lot about the past of the characters and how the whole situation in the Kingdom Hearts universe began.
Definitely 'Kingdom Hearts 1' as it starts the whole adventure. Then 'Kingdom Hearts: Chain of Memories' which bridges the gap between the first and second games story - wise. And of course 'Kingdom Hearts 2' to continue the main storyline. There are other games like 'Kingdom Hearts 3D: Dream Drop Distance' that add elements to the overarching story as well, but the first few are the most essential for getting the basic plot.
The main order considering side games too would be Kingdom Hearts: Birth by Sleep, Kingdom Hearts: Re:coded, Kingdom Hearts, Kingdom Hearts: Chain of Memories, Kingdom Hearts II, Kingdom Hearts 3D: Dream Drop Distance, Kingdom Hearts III. The side games like Re:coded add extra details to the overall lore.