the modding discussion channel https://discord.com/channels/1144933990676041768/1321898658702164030
But your problem is you cant save base game changes, you have to save changes to a mod. That said I am not sure how much you can mod them yet, there are some things like changing habitats you for sure can do already, I know it was planned for you to be able to edit the land itself and stuff but unsure if its been implemented, probably has been by now.