I would like to know if depreciation is calculated for monthly operating income statement.
If you can provide me a format that would be great

Yes, it is.

There are different methods for depreciation.
You need to figure out what depreciation method your company uses, then you need to get the cost of the depreciable asset, the salvage value of the asset, and the service life of the asset or total number of hours to be used or total number of copies to be made etc...

Once you have all this information you can calculate depreciation for your reporting period.