はじめまして。私はハナです。ドイツ人です。日本語を学びたいです。 *I think you don't have kanji for your name, if your nickname of italki is 花, you can use it, however, さん isn't needed. It's used when we call other person. So, I say ハナさん、こんにちは。 *To connect sentences, we use other grammar, or we separate in two sentence with the Japanese period "。". I hope this helps you and it's better to write in "notebook" page if you need corrections. Good luck!