The API to Big Query is well defined:https://cloud.google.com/bigquery/docs/reference/rest/v2/
There are a number of official client libraries, with Python being one of them:https://cloud.google.com/bigquery/docs/quickstarts/quickstart-client-libraries
It is possible to call c++ from Python with Boost.Python.
On the other hand, there are others in the forums who have C# code (with C# being a native client library), could probably interface directly to Big Query.
There may be others who have Python code for handling the IQFeed interface.
If all you desire is 1 minute Bar updates, it may be straight forward to use python natively to talk to IQFeed, decode the inbound streams, build the bars and send them to Big Query. I could maybe accomplish that task a s special project, if no others are available. The issue here is that if you are dealing with 100(s) of symbols, and depending upon their liquidity, there may be performance issues with handling the inbound streams.
Something to which I have not looked, IQFeed may supply real time bars. If so, then performance issues may not be a problem.
In any case, you will need some sort of server on which the interface code and the IQFeed client will need to reside.