I can't find templates

I am new to Hugo and I have a site that has:

└── content
    ├── service
    │   ├── _index.md # "title: My Hugo Blog" in the front matter
    │   ├── post-1.md
    │   ├── post-2.md
    │   └── post-3.md
    └── events #Note there is no _index.md file in "events"
                    └── service-1-events
                              ├── event-1.md
                              └── event-2.md
                              ├── event-1.md
                              └── event-2.md
                   └── service-2-events
                             ├── event-1.md
                             └── event-2.md
                             ├── event-1.md
                             └── event-2.md

In my layouts folder I have a folder for each service and each folder has single.html and list.html.
I created a new folder for events, and inside that event I would like to have a folder for each service, so that I can have events related to that service in that folder. content/events folder I created these folders but by default i get the list.html template for the events folder. not the nested folders.
In short:
I’d like to have events related to a service on this url /events/service/ => for list page, and /events/service1/event_id/ => for detail.html. Can anybody help me with that?

_index.md creates a list page. You want a list page for service-1-events? Put an _index.md INTO service-1-events, run hugo and see what happens. It should take the default list template and create one under /events/service-1-events/index.html.

If you mean to have one single list page for all events under service-number-events then have a look at the documentation for taxonomies.

Add a taxonomy for your events and create a list page for that taxonomy.

Thanks a lot for the answer. when I put the file _index.md inside the path content/events/service1/_index.md, the url example.com/events/service1/ shows the same content as example.com/events/. What I am trying to achieve is the url /events/ to show all the events in all the services, but events/service1/ to show events related to that service. Is the taxonomy the only way to go in this case?

The “rule” is, that once you have an _index.md in a directory you can’t have any in a subdirectory. So, doing the service1 and service2 list pages needs to be done with a taxonomy. I would put all events into one single events directory (maybe as leaf bundles - folders containing an index.md and the event info) and then link to the taxonomy for each event type.