The ignition switch is not the key and tumbler
The ignition switch is what the key and tumbler / Lock cylinder activate
Here is the ignition switch
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Ignition switch is located on the steering column under the knee guard … the key pushes a rod that activates this switch. Switch is adjustable on its mounts so it must be lined up properly so that aux / off / run / start are in the correct positions
Sounds like your alternator is not charging
When running you should have 14.2-14.6 volts at the battery
Bad battery or bad terminals could explain a lot with the issues you have