So, if you never did it you could try to make a powerbank from 18650 cells, just make sure to get good ones because those do tend to explode sometimes, then you get a charger circuit for those and a rectifier to generate the 5v for the raspi, probably one for the screen too that one seems to be 12v? In any case here's the plan:

1. Get a few 18650 cells (the good ones like samsung so it doesn't explode on you)
2. Charger circuit for those (kinda like this https://www.amazon.com/11-1V-Balance-Lithium-Battery-Protection/dp/B07JMY631D/ref=sr_1_7?keywords=18650+charging+circuit&qid=1639358928&sr=8-7)
3. Rectifier bridge to output to the raspi and the monitor screen (For the screen you can probably hook up the circuit directly to that board above, but for the raspi you need to make a step down and take 5v from it otherwise it'll burn)
   

Also sorry it took me so long, i was away from home today. hahaah