Grammarly is indicating I need to add a comma before often. However, I think it is not necessary since the phrase "often the data required is not available" is creating a subordinate clause with the text before.
Because in places like my region often the data required is not available, I want to learn the procedure to collect it in a real-life situation, which I can do in the fieldwork conducted this semester.
Remember that punctuation is not grammar; it does not exist in the spoken language. It is a set of conventions that are not universal.
As FumbleFingers implied in a comment, the sentence is quite awkward, and punctuation would help. I have not found Grammerly to be ideal, and you have not given its complete review of the sentence. But here is how I would punctuate your word order
Because, in places like my region, often the data required is not available, I ...
I’d punctuate it with that pair of commas because that unusually placed prepositional phrase of “in places ...” would be framed by pauses in spoken English to indicate a somewhat unusual word order. With a more normal word order, I’d punctuate it as
Because often the data required is not available in places like my region, I ...
I do not mind the unusual word order with “often” as a technique of emphasis, but then I agree with FF not to invert “required” and “data” because too many disruptions of the most common word order make a sentence hard to follow. So here is how I might revise your sentence
Because so often the required data are not available in my region, I ...
I would not object to this alternate punctuation
Because, so often, the required data are not available in my region, I ...