Will it be before next week?

Next week, you don't need to add or add before it. In means in …, at usually appears in pairs with home. Use the preposition on, on+ before the extended data "day of the week" to add a specific date, for example: Saturday; On+ day of the week +s: there is a plural form of the day of the week, which means that something is done habitually on the day of the week.