I'm not sure if this is the right place for this sort of advice, but I can offer some advice based on my experience writing research papers:

If you find one topic more interesting than the other, I would suggest writing about that topic. Often, it may be more intellectually stimulating to write about a topic that is less researched and examined (and can thus be harder) but that you're interested, versus one that is more researched and examined but that you're not too interested in.

If you have a general topic but have a hard time narrowing it down, you may want to focus on a central question and go from there. Maybe you read an interesting sentence in a reading, or the professor mentioned an interesting fact. Or, it can be out of personal curiosity, for instance, you may wonder what the attitudes were toward Kamikaze pilots in Japan, or how comfort women were received by Korean society during the war and in the years following. Pick a question that you are interested in, and then begin to do some research.

Of course, this question may lead you to formulate a different question through your research. But once you have a question identified, it's time to go through the previous research and primary sources about your topic, and then form a a thesis. My best advice to you would be to take quotes and ideas from the sources you pick, and be sure to include a page number! There is nothing worse than having a note and forgetting a page number, and frantically looking for it in a book.

Once you have all the research done and everything in place, you should begin the actual writing: outlining, writing, editing, etc. If your paper is particularly long, you might want to break the writing down into sections.

To give you a practical example, last semester I had to write a ten page history essay about a topic in Mexican Migration to the US. It was also my first research paper in a history class, so I was naturally nervous. I also study women, gender and sexuality studies, so I chose to write about the history of queer immigration, and how gay marriage may impact it. I was initially reluctant, and wanted to write about the Mexican Peso devaluation, but my professor was actually the one to suggest that I write about queer immigration instead. I am glad I did, as I managed to write an interesting topic. The research was a bit hard (as I expected), since most sources tended to cite each other (or so it seemed) but, in all, it was not too difficult because I was genuinely interested in what I was reading. I had enjoyed the readings in my gender studies classes, and it was very exciting to be able to apply the concepts I had learned in my primary major.

As for the writing, I found it much easier to write in sections. While the entire 10 pages seemed daunting, I ended up breaking it into sections and wrote what I felt was appropriate for each section. In the end, the paper came out to be two pages longer than I anticipated, and it was actually a lot of fun to write.

If you would like a book for this, I bought Rampolla's A Pocket Guide to Writing in History. It also has useful tips for essay and ID exams. I followed it very generally and I feel that it gave some useful principles for formulating a research topic and writing style. If you have the money, I recommend it. It's about $20 but you could probably find a much cheaper copy elsewhere.

Best of luck!

I wrote a post a while about how to develop suitable research questions here, which you might find useful in addition to /u/windowtosh's advice!

I don't want to be that guy, but in addition to the other advice please look over your writing. In this post you have a spelling error, misplaced period and some phrasing which could be questionable. I know this is just a post on the internet, but these things really do matter.

Remember that you are trying to communicate something in your paper and you have to pay attention to how you communicate as well as what you communicate.