'12 MB Pro Boot to Grey Scrn - Tried what I found in forums

Mid 2012 13" Mac Book Pro running OS that came out middle of this year (don't remember version). Currently boots with chime. After about 1-2 minutes, screen backlight comes on (blank screen), keyboard lights up, green light on CAPS toggles, and Apple logo on back of screen is lit up. Stuck at this.

If I let the screen and keyboard go black from this and then press a key, they light up again.

No spills since 3 years ago (Genius said one cell on trackpad was out, but trackpad started functioning normally after about 4 months). No drops. Was working normally, I shut down properly, placed in my briefcase, drove for 5 hours, booted up when I got to my destination. I initially got nothing, no chime. Got the chime and the screen/keyboard as described after SMC reset.

About 3 or 4 months ago, it started running very slowly. My solution was powering down every night. I also ran MacBooster at each startup, doing system clean up and another function (I think Boost). Following these steps, computer ran as quickly as when it was new.

Has a 1TB hard original hard drive, I'm using about 256Gb. Have active and updated anti virus/anti Malware programs.

Looking for thoghts on cause/recommendations/solutions, hardware vs software and if this is something I can fix vs paying for Genius.

I've tried the following:

Starting in Safe Mode

Toggling screen brightness

When on grey screen, typing first initial of user name, typing password, pressing enter

Press power button, press S, hold down power till shut off, restart

PRAM reset

Thank you in advance.