Water bath canning advice for marinara sauce please

We haven't canned for ages and lots of conflicting instructions found for canning quarts of marinara sauce and would appreciate some expert advice to set us straight.
Instructions seem to vary for amount of headspace to leave and water bath processing time, would appreciate your procedure for doing it and TIA

No experience with marinara and canning. However I do freeze it in one cup portions. Freezes beautifully, and tastes the same after I thaw it.

We haven't canned for ages and lots of conflicting instructions found for canning quarts of marinara sauce and would appreciate some expert advice to set us straight.
Instructions seem to vary for amount of headspace to leave and water bath processing time, would appreciate your procedure for doing it and TIA

Shel, get this book:
Ball Blue Book
It was the home canning bible for my family for several generations, and I have a copy myself.
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