How do I add a custom event/hook when an order is created/edited

[NiZZioN]

Hey,
I'm currently developing an integration with two systems and I have to send the order back and forth, that means that I have to send a REST call after every created and or updated order and that I have to update the order once a specific api call is triggered towards GLPI.

1. So for example if an order is created/updated in GLPI -> send post call to external api -> handle response externally with order information
2. So for example if the state changes externally -> post call to glpi -> update order with the response

How would I go about implementing such feature, what are the best approaches and how is it handled, I don't have much glpi experience, so any help would be appreciated.
Also I am wondering if it requires a lot of customization on GLPI end because from what I've read there are some hooks or events?
Any help would be greatly appreicated!

Best Regards,
Nizz