First off, if your cousin and his "step-brother" have the same father, they are not step-brothers; they are half-brothers.Now, your cousin is your cousin (first cousin) because he or she is the child of a sibling of your parent. Perhaps your cousin's father married his sister-in-law after a death or divorce. If so, the cousin's half-brother is still your first cousin. Or perhaps your cousin's father married your aunt from the other side of the your family (a sister of your other parent). If the half-brother/step-brother is the child of your aunt, he is still your first cousin.In any case, it is OK to date your first cousin if you want to. The questions may arise in some, but not all groups and locations, if dating goes further and becomes sexual activity. Some jurisdictions and cultures find that to be improper; others do not.
Your brother's cousin is also your cousin.
The English language does not use the phrase "cousin brother." The brother of your cousin is also your cousin.
A step brother's cousin is no relation to you.
He could be your brother. He could be a first cousin. If the uncle married into the family (Married the sister of one of your parents), the brother would not be related in any way and neither would his son.
You don't have to tell your cousin such things. If you don't know how to do it, don't do it.
He has sis-in-law from romania(he younger brother alan wife).
Your cousin's brother is also your cousin, but the cousin's wife is not related to you.
Your first cousin's nephew is the son of your first cousin's sister or brother. That sister or brother is also your first cousin, and the son is your first cousin, once removed. So your first cousin's nephew is your first cousin, once removed. Similarly, your second cousin's nephew is your second cousin, once removed.
Well, your cousin's brother is also your cousin, and a cousin's son is also your cousin.
Islam is one of those religions that believe it is acceptable to marry your cousin. It should be noted, however, that "cousin brother" and "cousin sister" have no meaning in the English language. Your brother or sister is a person who has the same parents you do. Your cousin is someone who is the child of your parents' brother or sister, or of your grandparent's brother or sister.
The brother of your wife's cousin is also her cousin. You can call either of them "my wife's cousin." You are not related to them.