The imperative in German is used for giving orders. There are two different forms of the imperative in German (depends on how many person you are addressing).
This form has also two different forms in German (addressing formally and informally).
For addressing one person informally you take the „du“-form (for a person with whom you are quite familiar – children, family or close friends).
For addressing one person formally you take the „Sie“-form (for a person you don´t know).
English: Come here
Translation: to come -> kommen
German (informal): Komm her
German (formal): Kommen Sie her.
Separable verbs as „anfangen“ (Englisch: to beginn) split off the prefix and the prefix is placed at the end of the clause.