Nobody can help you to supply words for such a personal statement. To be genuine, it must come from you alone. Once you've made a substantial first attempt, I'm sure that you will find many here to help you with your English. But you must first make the attempt.
To do this, use questions to generate the ideas that you wish to express. For example:
Extend this list with your own thoughtful questions. Answer your own questions in your own words. Just spill the words out on the page. Then reorder them for the sake of organization and clarity.
- What are some of the most memorable experiences that you shared with these folks you are now saying good-bye to? Come up with a list of at least three and then put these into your own words.
- What will you miss the most? Again, come up with a list of at least three and then put these into your own words.
- Where are you going? What will you be doing there?
Post the results of your first draft back to this thread. Your genuine self-expression will be sure to elicit assistance.