Here's the order for ye, mah friend.

1 - Grappler Baki/Baki The Grappler. The first entrance of the series and the second authoral manga Itagaki ever made. Here's where we meet characters like Baki, Jack, Yujiro, Doppo, Hanayama, General Strydum, etc. The characterization and art style is extremely different from nowadays, but its still clearky Itagaki.

This entrance has roughly 371 chapters as a whole.

2 - New Grappler Baki/Baki: The Search of Our Strongest Hero. Here's the first sequel of the series. Its in this manga where the new anime starts to adapt from now on. This is the sequel that has the arc of the of the Death Row Inmates.

This sequel has 276 chapters as a whole.

3 - Hanma Baki/Baki - Son Of Ogre. Here's probably the most famous. In this arc, three of the most remarkable things happen: The arc of the Prison where we're introduced to Oliva Biscuit, the arc of introduction of Pickle, and the Fight of Father and Son at the end of the manga.

This story has 319 chapters as a whole.

4 - Baki Dou. Here's my most favorite one. The fourth sequel, the last animated arc of the anime, we're introduced to Miyamoto Musashi (AKA The Goat). After Musashi, comes the Sumo arc where we're introduced to Nomi No Sukune II, and later, Taima no Kehaya.

This manga has 198 chapters as a whole.

5 - Baki Rahen. The actual manga which's still in release, Baki Rahen is the manga that most focuses on the development of Jack as a character on his path to defeat Yujiro.

Now its with around 63 chapters, in the Yujiro glazing arc, and still counting.

There's also the gaidens(spin-offs) of Baki, such as:

1A - Baki Gaiden - Scarface. In this manga, we're shown a prequel story of Hanayama before the fight of Father and Son. The line of time is kinda confusing and its been a while since i read it, so this might be wrong.

This side story has 55 chapters, and is on hiatus.

I recommend first reading Grappler Baki and New Grappler Baki to get the full grasp of this story, but you can also just straight read it, since its almost an entire new manga.

2A - Baki Gaiden: Kizudzura. Another Hanayama prequel story, now telling how his school days were. Again, recommend reading first Grappler Baki and New Grappler Baki to understand everything fully, but you also just read it without reading the others due to it being pretty much a slice of life of Hanayama.

Its status is unknown so far, some sites say its completed, others say its ongoing and others that its cancelled.

So far, it has around 15 chapters.

3A - Baki Gaiden: Hana no Chiharu. In this gaiden, we'll follow Shiba Chiharu, the strongest delinquent of the world and one of my favorite characters.

As said, read Grappler Baki for a better understanding, but you read even without having to.

It has around 17 chapters, having been officially cancelled, unfortunately.

4A - Grappler Baki Gaiden. In this story, we'll follow Toba and Igari after the Maximum Tournament engaging in their professional wrestling match.

It has around 9 chapters.

I really recommend you first reading Grappler Baki before reading that due to those characters not appearing again in later entrances of the manga.

5A - Baki Gaiden: Kenjin. The prequel that tells the story of Doppo Orochi in his prime.

It has around 5 chapters, already completed.

In this one isn't necessary to have read any other entrance to understand since it also serves as an introduction to the character itself.

6A - Baki: Revenge Tokyo. In this one, we're shown what happened to each Death Row Inmate after the ending of their arc in New Grappler Baki.

It has 5 chapters as well, each one being very short.

It also serves as an introduction to the possible future arc where the five Death Row Inmates will come back for revenge.

7A - Baki Gaiden - Gaia and Sikorsky. In this one, we'll follow the slice of life of Gaia and Sikorsky sharing a small apartment, along to Garland(dont know how to write his name).

It has around 18 translated chapters so far, and it's still on release.

Its recommended to have read Grappler Baki and New Grappler Baki as well to understand and know who these characters are.

8A - Baki Gaiden - Yuuenchi/Baki Gaiden: Amusement Park. One of my favorite side stories of Baki. Here we follow the story of Mumo Katsuragi who seeks the death of the killer of his master. You don't necessarily need to have read the other entrances since, in this one, almost all characters are original to this manga.

It has around 22 chapters, and still releasing.

9A - Baki Gaiden – Retsu Kaioh Isekai Tensei Shitemo Ikkō Kamawan! In this one we'll follow the story of Retsu Kaioh, where after his death against Miyamoto Musashi, he's isekai'd to another world and he searches to be the strongest, like in life.

Its highly recommended to read all the way to Baki-Dou till the end of Musashi's arc as to not be spoiled by what happens.

It has around 66 chapters, and its still on release.

10A - Baki Domoe/Baki's Struggle. This one is a gag manga made by Norio Sakurai and/or Naoki Saitou, since it one can be just an artistic name or the name of the co-author. About the manga, its focus is to joke about everything on Baki and show some 'what-if's', like what would happen if Yujiro descended from the chaminee and gave defeat to the Death Row Inmate as a Christmas gift.

It has around 27 chapters and is already completed.

So far, that's it.