Shalom, my name is Thomas, I am interested in converting to Judaism but I am of Jewish blood but no one in my family is Jewish, my family is entirely German and my surname is Groskopf which is a Yiddish surname, I am wondering about going about this?

If you can verify that your mother's mother's mother's... were Jewish, than you are Jewish and there is no need to convert. On the other hand, if you think you may be Jewish because of your father's Jewish sounding last name, than you are not Jewish (Judaism is determined by one's mother), even if you may have some Jewish roots. In general, it's very difficult to be Jewish, and you are better off being a Noachide, observing the 7 basic commandments received by Noah, and it's much easier to go to heaven that way, rather than having to observe the 613 (!) commandments of the Jews (plus many rabbinic commandments). If nevertheless you wish to be Jewish, consult your local orthodox rabbi personally.