So this morning I started having this exact same issue as the video in this post
https://www.reddit.com/r/computerhelp/comments/fy06rg/i_have_an_acer_nitro_5_an515_when_i_power_it_on/Didn't matter if the computer was plugged in or not. I removed the 8GB ram stick and just left the 4GB in, now it will boot up but the HDD clicks and only the SDD is detected.
I also noticed when I was finally able to log in that the battery wasn't charging (stuck at 38%) and if I removed the charger it would immediately die.
Now it's randomly started charging again and will run with the charger unplugged.
I can't tell if this is a RAM issue, a motherboard issue, a HDD issue or a battery issue.
Any help is appreciated, thanks!