Engine Cutoff, 1992 Ford E350 Econoline Chassie, 460 gas

What crasster said ^^^
The key to troubleshooting this will be gathering enough information. For example, you say that there is no click or other attempt to start. Do you have any other electrical power, for example headlights, fan blower when you turn key to "ON" position, that sort of thing? The good news is that since the issue disables the ignition system AND the starting system, that already reduces the number of possibilities.