It is possible to terminate probation early. Courts usually require a showing of need and change in circumstance not present at the time of the plea.
You can certainly get a passport, but travel out of county will require prior approval from probation or the court and travel out of the country will certainly require approval from the court. The court could set limits on your travel. When you make the request of the court, simply tell them where you plan to go and why and hopefully it will be approved.