I would get my college degrees; bachelor's, master's and doctorate, probably in something to do with literary arts or history and then hopefully become a college professor and definitely an author. I would be involved in movements for social change.
In high school my plan for my life included never marrying, being an author, having a little cottage with lots of flower gardens and lots of pets. If I could go back and know what I do now and not have Watchtower influence, I would try very hard to have that life and be a college professor as in above paragraph. But I know now I would never be able to drink and should stay away from recreational drugs - being a recovering alcoholic, I know those things are a life destroyer for me.
But out of this life I have today, I have three wonderful sons and four grandchildren, one more on the way in the next week, and a very happy life, so no regrets.