OK so here’s the deal. I recall once trying to delete my game environment (my RPG game) and replacing it with a new one, and to no one’s surprise, it broke the game and made it unplayable (and I still don’t understand why). Back then fortunately I didn’t save it by accident, but I don’t want this to happen again. So my question is:
If I were to re-design my game environment, what should I be on the lookout for before going reckless?
That’s a difficult question to answer, especially not knowing what, exactly went wrong.
First things first before you start redesigning your scene…
Open up your Source Control program (You ARE using Source Control, right?) and commit your project before you start. If you mess up, all you have to do is revert to the saved commit.
For a scene to be playable, it needs to have the Core prefab, which of course, at a bare minimum contains the Player, and a Follow Camera (we actually also put our UI in the Core prefab, and it’s often useful to keep an EventHandler in there, then you don’t have to worry about forgetting to put one in the scene.
Beyond that, you need a terrain, which should be on the Ground Layer, and any GameObject in the scene you might want to be able to walk on should also have he Ground Layer set.
OK not to be the weird one in the group, but I tried using git once and I didn’t know how to commit or repo or any of that… Hence why I’m walking on eggshells right now 
(I’m doing my best not to make any wild errors until I can get help committing to git 
)
Fortunately, we have a course for that!
I cannot emphasize enough
Git is not for just in case you create an issue that makes your game unplayable, git is for WHEN you create an issue that makes your game unplayable.
It also lets you work on different aspects of a project at the same time, by switching branches, and then when an aspect is ready to integrate in to the full game, you’re able to merge the branch into your primary branch.
And of course, if you’re ever working with others on a game, git and nightly checkins are pretty much the only way you’ll keep from going crazy. 
@Bahaa I tried several times to learn Git by watching you tube videos and it did not click. Then I got the Git class on here. It was very helpful. I am now combining the RPG and 3rd person combat systems and I am confidant that if I mess up, I can revert to a clean commit. As an old guy learning this as a hobby, I can not stress enough how helpful the Git class was.
As a 25 year old man who made countless mistakes and is quite tired of them, I’m just waiting for the course on Udemy to go on a discount so I can buy it (and then I can freely do as many errors as I want). Hopefully I don’t do anything stupid by then (for now though, do you know how I can save the entire project as a backup on my PC?)
Wait until you reach 60 years to count your mistakes. Saving a project is easy. Just copy the entire folder and then give it a different name. Before I took the Git class, I had backed up my project from the RPG class by copying the folder and renaming it with the date.
Believe me, my mistakes come nowhere close to yours, or anyone who lived for significantly longer than me. I’ll go save my project as well, hopefully nothing bad happens to it
Keep up the positive attitude! You can handle this!
Thank you edc. Wishing you nothing short of the best as well 
You can always zip up the project folder, and remove the Library folder (because it’s easily rebuilt).
You can actually just zip up the Assets folder, now that I think on it.
If you need to revert,
Udemy’s always having sales, so keep an eye out.