Well, my speech is short. [STRIKE]is[/STRIKE]
Peace be upon you/with you. I am Roba, from Palestine. I am 23 years old. [STRIKE]Study Dentistry[/STRIKE] I have not finished my dentistry studies yet. I am happy to have my presence with you as a supporter and organizer of the total. Thankful good host you. Wishing success for you and me. Thank you for all.
You have all the relevant information there, but you need to work on your punctuation, capitalisation and verbs. I have corrected/added the punctuation in red above and added some extra words.
However, for the whole speech, here is what I would suggest:
Peace be with you (I am assuming this is a traditional beginning to a speech in your country). My name is Roba, I am 23 years old and I am from Palestine. I have not yet finished my dentistry studies. I am happy to be here as your organiser/co-ordinator and I hope that we can support each other. I wish us all success in the future. Thank you.
I'm not sure what you meant by "Thankful good host". Are you thanking the person who is hosting the meeting? If so, you can add "I would like to thank [name of person] for hosting this meeting.