Hello soulcalm17

[Paleophyte]

Very much no. Zeus was first amongst equals at best and had little to no power in his brothers' domains. The Greek religions, which the Romans co-opted, were never even henotheistic or monolatric, much less monotheistic. We have that from both Greek, Roman, and early Christian sources.

What we call Roman religion lasted a long time and changed a lot. You're certainly right that Zeus was one of many. 

By the time we get to Marcus Terentius Varro (116–27 BC), Jupiter is gaining in importance, to the point where he far overshadows the others. Since the philosophy of both Plato and Aristotle posit a highest power - a prime mover ontically different from Apollo or Venus - later writers begin to associate this prime mover with Jupiter. 

As for example in Vergil's Eclogues, where he says "all things are full of Jove; he keeps the world..." 

But there was never a central authoritative source for what people had to believe, so the idea of Jupiter as prime mover no doubt existed alongside other versions as well.

Hard to reconcile Zeus with a Prime Mover given that he was widely recognized as the youngest of the offspring of Cronus and Rhea, themselves the children of Uranus and Gaia.

What we know with reasonable certainty is that virtually every Greek city, town, and hamlet had their own patron god, or goddess and sometimes more than one. We don't see them giving those up in favour of Zeus, which is what we'd really expect from any move toward monotheism.