Is there any way we can run multiple APIs in a single query and get as a single dataset ?
Query results might be an option as an alternate. But I want to check if anyone tried to use multiple APIs in single query and if they are successful.

You haven’t given much information about your use-case. But I assume you mean using the JSON data source? If you mean the JSON data source, no: each query issues exactly one API request. And the query results data source is the official way to combine multiple requests.

However, since Redash is hackable, you could also fork the JSON query runner, using it as a base for a custom query runner for your API. Happy to answer questions about how to do this if that would be useful.