Welcome to this platfrom, Mike

I agree with @mariekedestip's comment that you do not have to choose any one field. Many Steemers, from Minnows to Whales, blog about a wide range of topics.

I post about the current economic horrors, then I'll post some photos, and move on to English Vocabulary and great lyrics from classic rock music.

You can do the same. As long as you have a genuine interest in a subject, and if you are willing to spend time making quality content, then do what you love.

Do it well, and others will notice it, appreciate it, and upvote it.

Best of luck, and Full Steem Ahead.