You would answer by telling them when your birthday is - we don't have a way to know your birthday so we can't translate it into Spanish for you.
You would answer by responding with "My birthday is...." or "Mi cumpleanos es...", but since only you know what your birth-date is, it would be impossible to translate the exact date.
Mi cumpleaños es el [fecha].
No es tu culpa.
"Tu es gordo" is not correct Spanish. "Tu eres gordo" means "You are fat" in Spanish.
"Cuanda es tu cumpleamos" does not make sense in Spanish. "Cuándo es tu cumpleaños" is the correct phrase, which means "When is your birthday?"
Mi nombre es...
"Tu es en la casa" is incorrect grammar as it mixes French and Spanish. In French, "tu es" means "you are," and in Spanish, "en la casa" means "in the house." The correct phrase in either language would be "tu estás en la casa" in Spanish or "tu es dans la maison" in French.
No es tu culpa.
¿Dónde es tu casa? or ¿Dónde es tu hogar?
Cuando es tu cumpleaños?
"Cuanda es tu cumpleamos" does not make sense in Spanish. "Cuándo es tu cumpleaños" is the correct phrase, which means "When is your birthday?"
Mi nombre es...
Tu nombre es
¿Cómo es su / tu / vuestro país?Como es tu país (Not a question)
In Spanish it is usually "¿Cuál es tu número de teléfono?
If you mean… ¿Cuándo es tu cumpleaños? … then that is Spanish for, "When is your birthday?"
¿Quién es tu actor favorito? in Spanish means "Who is your favorite actor?" in English.
"Quien es tu familia" means "who is your family" in Spanish (you do not use "es" in that sentence)
"Cual es tu mes favorito?" means "What is your favorite month?"