Hi , Lena Siegmund
Check this tutorial online: https://www.youtube.com/watch?v=w4-DEiZVZTA
or check this learning path: https://academy.mendix.com/link/paths/56/Create-an-App-with-Advanced-Page-Building
In module 3 there is a detailed explanation for implementing a Custom Login Page
Good luck. I hope it will help you.
Thank You .
K. Ravi Kumar.
Hi Lena Siegmund
Step 1: create a page choose login
step 2: go to app security enable anonymous user role
step 3: go to navigation Tab to set login page on authentication
Step 4: after set role based home page for anonymous user look like this below image
step 5 : give page access look like this
If you have any questions, feel free to ask.