REST APIs in API Engine

I just want to clarify the capabilities of the API Engine, to see if it can do what I need.

Currently, I use hosted nodejs web scripts in the file section of Backendless mBaaS, and called them in a REST way.
I was told this same functionality is not in the stand-alone Backendless. However, it appears that it has now been included in the latest (stand-alone) release - is that true? If so, how is it implemented, using the file method I use now, or using API Engine over the top of what? If API Engine, does that mean I can design and create a REST API? And finally, if I can create my own REST API, can it be designed to only use GET and POST methods (as the language I use doesn’t support PUT, PATCH OR DELETE), or provide an override parameter, e.g. overridemethod=PUT (like the way firebase in Google allows?)

Lots of questions, and thanks if you can answer them!

I was told this same functionality is not in the stand-alone Backendless. However, it appears that it has now been included in the latest (stand-alone) release - is that true?

No, it is not, the node.js support for hosting scripts is not included into the Standalone edition of Backendless.

If so, how is it implemented, using the file method I use now, or using API Engine over the top of what?

API Engine is included with the Standalone Edition of Backendless (if that is what you’re asking)…

If API Engine, does that mean I can design and create a REST API?

With API Engine you write your Java code and the REST APIs are generated based on the methods available in your service code.

And finally, if I can create my own REST API, can it be designed to only use GET and POST methods (as the language I use doesn't support PUT, PATCH OR DELETE), or provide an override parameter, e.g. overridemethod=PUT (like the way firebase in Google allows?)

REST Routes are generated per the rules documented here:
https://backendless.com/documentation/api-engine/apieng_rest_routes.htm

I should have clarified, can you do the executable code, behind the REST API, with NodeJS rather than Java? I though I read that, or maybe it’s coming soon?

Yes, the same support for provide for Java is coming soon for Node.js as well.