Would You Please Help On Identifying The Medal

Here's the designer/sculptor (at least of the obverse):

https://en.wikipedia.org/wiki/Oscar_Roty

Since he died in 1911, I can't say as he designed the reverse, as it has the dual dates on it.

I'd guess its a commemorative of 25 years of a place called Montrouce.

Civic medals are still a big deal in France, and the Marianne figure on the obverse is still used today as are similar designs from other artists long dead.
Your medal is marked BRONZE but appears to be silver coloured. so it's presumably silver coated, a process called bronze argente. You don't give its diameter but I suspect that it will be either 30 mm or 50 mm.
It's good that it has the original case although it's badly in need of recovering.

Not worth as much as you might expect, because there really are a lot of them on the market. 30 mm maybe $20-25, 50 mm $25-35.