I'm not sure who 'helped' you with that, but every single one of your German translations is wrong. OK, here we go:

>Fuck me.
Fick mich (fikk mik).

>I want to fuck you.
Ich habe Lust, dich zu ficken (ik habbe loost, deek zoo fikken).

>Let me suck your cock.
Ich will deinen Schwanz saugen (ik vill dinen schwahnz saogen sort of like sow
(like the pig) and guh - ik vill dine schwahnz sawguh.

>Suck me.
Lutsch mich (lootsh meek).