In developed countries, estimate $10,000 USD per employee per month. (
Here is an easy to read breakdown.) An extremely rough estimate of how long a first game takes to develop is 2 years. If a designer tells you it will take 1 year, it will really take 2.
A common estimate for marketing costs for an indie game is $50,000 USD. (See
here for rationale.)
The costs to publish on the stores are relatively insignificant in comparison (e.g., about $100 USD each).
These are averages. You could end up spending more or less, but they come with their tradeoffs.
Note also that commercial game development is risky. Watch Mike Rose's GDC talk:
It's from 2018, so it's already outdated, but it will give you an overview of the landscape.
That said, even if it's not profitable for the vast majority, making games can be artistically rewarding.