i would just like to know how do you say it the right way
Do not use 'miles dei.' That means 'soldier of God,' and to a Roman, a soldier was a trained, disciplined fighting man, a member of a legion. A warrior (bellator) was an udisciplined, untrained barbarian. There are two different words on purpose. Don't assume thet're synonyms.
Miles means "soldier", which is basically the same as warrior, and Dei means "of God".
"bellātor deī" or "mīles deī"