Karaniya metta sutta is there.
but if you learn how to pronounce the letters you can chant correctly, there are several ways to chant and so long as the pronounciation is roughly correct so it can be understood what word you are saying then there is no hard and fast way to chant, I like the Abhiyagiri chanting personally, but each to their own.
the only thing to remember when doing it is a group is to try to match the pace of the leader.
He who knows only his own side of the case knows little of that. His reasons may be good, and no one may have been able to refute them.
But if he is equally unable to refute the reasons on the opposite side, if he does not so much as know what they are, he has no ground for preferring either opinion …
He must be able to hear them from persons who actually believe them … he must know them in their most plausible and persuasive form.