Collaboration is behavioural, not a process or system. As a behaviour, it can’t be taught. It’s something that some people exhibit and other people copy. It’s Homo Imitans  more than Sapiens.
If you want to create a collaborative environment, you would waste your time preaching collaboration. You need some good collaborators who collaborate and other people can mimic. Simple. If you don’t have any, you may have to import them, transplant them, inject them, parachute them in. It won’t happen otherwise.
Collaboration won’t come down from the sky. Unless you have a 10 or 20 year plan, you can’t afford a slow change in the culture. Not now.
These are other things you may want to do if you want to waste your time.
A cultural assessment of the ‘readiness’ for collaboration
An in-depth analysis of why there is not much collaboration in the culture
A team building, or hundreds of them, that magically will trigger collaboration in a non-collaborative environment
A collaboration training package
Putting collaboration and teamwork in the value system, say you value them and then pray.
Implant collaborative people who do things by collaborating. Be sure they are visible. If they have high social connections, bingo. Protect them.
Inject the practice, social-engineer it, if it did not exist, make sure people copy, create a critical mass, spread the behaviours, make collaboration normal. Then, have any discussion you want about collaboration readiness and why it was not there in the first place. Only then.