installing marlin firmware

#1
I'm trying to install the newest marlin firmware so I can use the BL touch. I don't have the new LCD screen, just the original that came on the printer a couple of yrs ago (gmax 1.5+)

The after going through the steps to install marlin (followed the youtube video), the installer says it downloaded, but the printer is non responsive. there is no info on the LCD screen.

What do I need to do to get marlin properly downloaded?

I haven't connected the bl touch yet, or installed the jumpers per instruction (because I didn't get any with the touch, have to get some), could that be the issue?