Looks like default limit is 25 and max you could do is 200? How to get all projects?
That's correct. You should do it for offset=0 (of course, this is not needed for a value of 0), then 200, 400... until you got all the projects.
Just a small reminder/disclaimer, the REST API is currently not supported for Customer or partner use as this is still under active development. This is documented in https://docops.ca.com/ca-ppm/15-2/en/reference/rest-apis or the equivalent page for your PPM release.
Still, if you want to use it, understanding the consequences, you can use the "offset" parameter, so that it starts in the nth project, i.e.: http://<yourserver>/ppm/rest/v1/projects?offset=X
The "limit" parameter is defaulting to 25 and the maximum is 200 (valid range is 1-200).
The full list of parameters available for your release (they differ between releases), along with an explanation and even a method to try them on PPM itself can be checked in http://<yourserver>/niku/rest/describe/index.html (open this site after being logged into PPM).
So in that case with limit of maximum 200 you do multiple batches with Offset N if you need to pull more.
Have you considered using the WSDL?
XML might not be so fun, but it works
Retrieving data ...