Looking to start editing and in need of advice

As the title says, I'm looking to dive into the world of hex editing. The game that I'm looking at is Suikoden 2 (I've done some editing before but with editors that other people have created, so i'm in the dark for this one). 

Basically, I'm just looking for some advice on what program to look into (for instance I've heard about HxD and I'll be looking at that after I post this). Or some other program that I can look into? I'm not looking to do any over the top changes, just adjusting stats for enemies/maybe some of the playable characters. So just point me in the right direction and let me go at it, and of course any additional advice/insight is always welcome.

Unless there is documentation on where enemy and player data is located, you're going to have reverse engineer it yourself. Seeing as you've yet to familiarize yourself with hex editing, the learning curve will be steep. I don't say this to discourage you, just to let you know what you're getting into. What may seem simple is not necessarily easy, and if you're expecting easy, you'll likely quit before you can get anything done.

I'm sorry I can't provide any concrete advice. I'm not familiar with the game, nor aware of any community focused around modding it. I think your best bet is finding any documentation available for the game and going from there. And get acquainted with the basics of using a hex editor, hexadecimal and binary representation, addressing, etc. 

A good way to start if you're lost is to ask the dev who created the Suikoden 2 Hardcore patch, which debuggers he used to reverse engineer the rom addresses, and whichever info he already has (if he's willing to share it).

https://www.romhacking.net/hacks/3303/

From there on, second what seibaby said. The very basic two tools you'll need is a hex editor of choice (HxD is a good one, I personally like Hex Workshop because of its compare function but it's not free), and a debugger, where you find out a ram address, add a breakpoint to see how or where it us executed, read or written, then trace back and reverse engineer your way thorugh until you've documented a routine that you can change into whatever you want. In the meantime, you'll need to gradually learn the programming language (assembly, mosy likely) that the gane was coded into.

Hope this helps!