My 2018 Silverado 1500 just started doing the same thing. It began after I attempted a remote start and it tried to turn over and quit. I then used the key to start it and it would not do anything. The dash lights were all on but there wasn’t even a click to the ignition. Tried to jump start it and that didn’t work. Finally got back in the truck with the jump start and put foot on brake and it started.
Happened again two days later after no problems for 2 days. That time a guy who worked as a mechanic who saw me having a problem suggested clicking the key 3 times as if to just turn on the radio and then stepping on the brake and then starting. It started.