you could create the layout.tsx for each route
/app/layout.tsx <-- root layout
/app/(home)/layout.tsx <-- index page layout
/app/(home)/page.tsx <-- index page
/app/page1/layout.tsx <-- layout for page1
/app/page1/page.tsx <-- page1 page

Also, layouts at a higher level are always inherited, so to avoid that make sure to group your routes taking into consideration the different layouts for each group

when I don't delete /app/Layout.tsx Part of the background color remains white. looks like i need to delete it too

the app/layout.tsx is required, it will auto create it for you if you don't have one

in your case, you should keep it as simple as possible

Okay thx