"Is the month of March in the winter?"
(No, it is in Spring!)
"Is the month of March in the winter?"
Since "el invierno" is winter, your choice of months could include "diciembre", "enero", "febrero" and part of "marzo" depending on how many letters it is.
It means "in what season is the month". Probably better to use "ser" here. "en que estación es el mes?"
Marzo means March in Spanish.
You can say "Mi cumpleaños es el treinta de marzo".
El Mes = The Month
In Spanish, March 24th would be "el veinticuatro de marzo"
January
'El invierno' is 'Winter'.
el invierno
summer.
"El invierno" is "winter" in English.
"El mes" significa "the month" en inglés. "El día del mes" quiere decir "the day of the month" en inglés.