From my experience, with no experience of making games
With assets are currently available, you can make a scene in roughly 30 minutes. i was able to throw a couple of scenes together quick because i was able to understand certain things.
With no knowledge, i can see a scene being made in like an hour.
Add more time if they need to have a prop made, or certain object made if it hasnt already.
Add more time on animated scenes.
Once scenes are made to the liking, then come rendering. depending on the system you have rendering, at a decent resolution and graphics, can take about 3-6 hours.
More, if there are a lot of objects within the scene.
So with that info, you have to think about how some games are. the low end games probably took no more than a week to actually make. others like Eternum or TLG takes 3,4,5,6 months its depends on the scenes and what is going on with the scenes