I am not a professional teacher.
My sincere(st), heartfelt apologies go out to every (person) one whom I might have offended(for my regrettable) by use of (very inappropriate) abusive language and (for my action) indecent action. (I would like to apologize to you.) I’m sorry for so many things that I’ve done. I have made mistakes,( and for them, I am sorry.) I’ve hurt people without (meaning to) any reason and done many things (some) out of spite. And I’m really sorry for those(that). But I’ve learnt from all (of that) my follies and today I’m a better person(for all of it). (is it proper way to apologize in the email? Or is there any better idea)
Even though I will miss my colleagues and the company, I am looking forward to this new challenge and (to) starting a new phase of my career. I wish you all success in the future and am grateful for the opportunity of having to work with you.
I can be reached in (at) my personal email address myemail @ yahoo.com. Please keep in touch!
Thanks again for everything and best of luck to you.
(i) delete words in brackets to avoid repetition and use of inappropriate words.
(ii) The new words used here have been hibhlighted.