You should find it helpful to read through IRS Publication 527 at https://www.irs.gov/pub/irs-prior/p527--2019.pdf
It explains things such as depreciation, mortgage interest, property insurance and other allowed rental expenses you can claim. It also explains how losses get "carried forward" when your rental losses exceed your rental income. Its quite common for long term residential rental property to show a loss "on paper" at tax filing time, each and every year you are renting out the property. So understanding how this is dealt with can help you keep track of things and give a little piece of mind.
Now it's not like you nead to read the entire publication in one sitting. Read a bit, take time to absorb the information that applies to your specific situation, then read some more at another time.
