@crazycells yup.
You can find integration docs here (tl;dr you need to implement WOPI protocol for file access. Which will also work for most other web-based document editors, since that's basically the industry standard. OnlyOffice offers their own API as an alternative, but also supports WOPI. You can find an example server in Node here)
Install docs are here - from my understanding their primary distribution method is docker, but they do offer native packages if you prefer (looking at you Discourse with your docker-only yet for some reason linux-only installation using bash scripts)
