Good day

I am a beginner to trading and would like to start building components for a trading system.

There are some questions that I have regarding reading real-time data and performing transactions.

I know I need data to get into my black box and trades will appear from the other side.

I found there are data providers and brokers, who can sell you data OR allow you to do transactions.

I would ideally, like to minimize my start up expenses (and commitments) and develop my own trading system (which nullifies most http only brokers/providers). What are my other options?

Are there (free/cheap) real-time data providers around? How does a person read the data, is there a fixed format/protocol?

The second query I have pertains to performing transactions - how does a person integrate your trading system with a brokers system?

Do most brokers allow this? Are there any helpful brokers who support this functionality? Personal recommendations with regards to the above would be appreciated. I would use google, but I don't know what to start searching for! Even if you say, go look for "x y z", that will at least be a starting point.

I appreciate your assistance

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