Where can I find Documentation on Rest APIs limitations for data upload?

Summary:

Where can I find Documentation on Rest APIs limitations for data upload?

Content (required):

Where can I find documentation on:

1. Payload size limits when calling Rest API

2. Limitations on number of "patch", "Get" calls on the API.

3. Number of messages during a time frame

Version (include the version you are using, if applicable):

Cloud SaaS 22D

Code Snippet (add any code snippets that support your topic, if applicable):