I do something like this for work. I’ll share what I use. Take what works for you, leave what doesn’t. My feelings aren’t hurt.

Hardware: I have two TVs that are driven by Amazon Fire sticks. The software is an Android app, and we picked up the sticks on sale for $20 each. I’ve not tested the software on other hardware, but it should work on any Android based device. I have plans to switch to Android on a Raspberry Pi or similar. It’s only matter of time before Amazon breaks my setup, but for the time being (and for the last two years) this works without issue and was extremely cost effective.

Software: I want to recommend “Slideshow” by Milan Fabian. It’s an incredibly full featured slideshow app that will display anything that you throw at it (image files, videos, PDFs, spreadsheets, and more). It can also display web based things like a webpage or YouTube video. You can set timers so that certain content is displayed certain times of day. You can set times and dates so that content that is no longer relevant is no longer displayed. My description here really doesn’t do it justice. You should check it out.

My use case: I work for a school that is in a shared space. Beginning at 7am, the TVs show a slideshow of announcements from the school. It also cycles a music playlist of MP3s that are uploaded to the device. At 4pm, the TVs switch over to a web-based dashboard of where individual classes are in the building and which supervisor is closing the building (I built the dashboard in Home Assistant and it is unrelated to the Slideshow app). At 6pm, the screen goes black and the music shuts off until 7am the next morning. Because we share the space, there is a different slideshow that shows on the weekends based on what that group wants to display. When Monday comes back around, it’s back to my content. My team builds our slideshow in Canva and then pushes it to the device, but you could easily use Google Slides.