At some point in the mortgage process, you’re going to be searching for a mortgage calculator to figure out your proposed payment.
You can see how monthly payments on mortgage loans are truly calculated using the real math, or you can simply find a payment calculator that does all the work and tells you nothing about how it comes up with the final sum.
Just make sure you use a mortgage calculator that considers the entire housing payment, including taxes, insurance, HOA dues, and so forth. Otherwise you’re not seeing the complete picture.