app for rasberry pi

to have a "informations system" where we can manage to show background picture and text on a raspberry pi zero or or similare hardware together with a 7" display or other size. I want to send messages/text/picture from a website or mobile app to the display. The design and function of the solution will winn over hardware solutions. Other display solution (like e-paper) are also interested for same system solution. want to be able to manage templates with text and picture (other widgets as weather and clock) are also welcome but not a must for the version 1. The templates must be able to be set by time (schedule) examples of template texts 1. Welcome (allways when no other message) 2. Lunch break (to be scheduled every day like 11:30 - 12:30) 3. Today we welcom "Mr or Mrs who ever) Looking forward to all sugestions. Attached are sketches of how it could look