There are websites that publish obituaries or you can also write one in your respective social media accounts. If you think you can’t afford publishing in a newspaper, you can always try the internet. Putting an obituary in newspapers can be costly (the expense varies, but mostly newspapers charge you depending how many lines does your obituary consist) so consider this first in writing an obituary to your loved one. Catholic obituaries have mostly the same format with other obituaries so writing one is not difficult.
It contains some brief details about the person and the dates of the services/masses which will be held for him. An obituary is basically a notice in newspapers or some websites that someone has died.