Why is my new LCD replacement not working

Hello all—I took on my first ever DIY apple repair project. I have my old SE, which just up until recently I was using fine until the digitizer and home button were both problematic.  Right at the same time, my friend also had just stopped using her old, cracked (MAJOR cracks!) SE.   Which works fine, but needed a new screen.

Perfect timing, because then I had two SE’s at my disposal, to repair for my daughters (age 10 and  7)  to be able to use for iMessage/facetime their father and grandma…and music playing (very much into them being able access/use Spotify and explore music as much as possible… the only things I will let them do, as they are NOT getting actual cell phones until they are in either 1) high school and have a job or 2) when they go to college (but that is another topic altogether