Why does my display not work via HDMI?

My grandma gave this this computer a while ago because she broke the screen and gave it to me saying that if i could fix it, i can have it.

I’m not really interested in repairing the broken screen but I am interested in accessing the files. The only way i can think of doing this at the moment is to plug it into my tv via HDMI, however when I do, I receive no signal.

The HDMI port seems functional on the computer and is functional on my roku tv as i usually use it for my playstation, the HDMI cable is also working.

The computer does charge however it seems like the power button doesn’t work and i’ve noticed a rhythmic beeping noise which is likely the battery or some other component but i find it a bit odd. The display also randomly flickers black on the computer but that is presumably because the screen already being broken.

I already posted this on Reddit here where you can slightly hear the beeping noise i referred to earlier.