Since you put so many conditions in one sentence, all conditions must be true to give a yes answer.
Therefore no, since ONE of the conditions isn't necessarily true.

For your second sentence, one would need a schematic and a better description.
IF you are talking about having the switch unplugged and measuring continuity between various terminals, then STATE that you are going from terminal to terminal.
When you say "lights" etc., one doesn't know if you mean the light wiring or light terminal.

Without knowing what tractor this is, in order to see if a schematic is available, you might want to tell us that info.

Also break your questions down to ONE condition at a time.

To clarify your first statement.
You may get 12V through the solenoid using a voltmeter, but the contacts may not be capable of carrying sufficient current to spin the starter.
8 penlight batteries = 12V, but it won't crank an engine.

A much simpler test of the solenoid/starter motor is to simply jump 12V to the small terminal. IF the engine cranks, battery, solenoid & starter motor are good.

If it doesn't, one or more are bad, assuming the engine isn't locked up.

You are permitted to use the same thread for continuing the pursuit of the same problem.
It is not helpful to create a new thread for every question.
for instance, the question(s) today would have been better off if they had just been added to one of your other threads where we were already answering questions.
As a matter of fact, the link below takes you to a thread that you really should have stayed with for additional questions.

Here is a link that might be useful: In last week's episode we saw...

Thanks for your reply Bill and also for your advice Mownie