I need some help with auth0 addon SamL 2.0

Hello, I’m an OutSystem Developers. I need some help with the use of auth0 SamL addon 2.0
So i was working on Idp to make an single singin(SSO) for my application. Some tutorial online suggest that i should use auth0 samL addon to get the required certificate and stuff. I follow them but since they skip through the part what to put inside callback url and logout, i don’t know what to do
After a few time of research, i managed to input the data of the Application callback URL(Like the img below, but i still don’t know if it correct or not)


Here is my question
1.When i try to perform login using Idp, it redirect me to some kind of a login screen using password with this warning, what is it? Can someone help me how can i fix it?
image
2.When i try to logout, what am i suppose to put into the callback part? I’ve tried a whole link that direct to the login page, didn’t work. the original link that somewhat foo/logout(don’t even know what is it, didn’t work. Can someone please help me)
Beside if i set the application callback URL like that, it might cause me some trouble since i have at least 3 environment like dev, test, prod,… how can i config it. Thanks you all in advance