。
I plan to take two days off next week.
Literal
Next-week 2-day [possessive-の] rest [object-を] take [intention-つもり] is.
休みを取る ('to take a break / take time off') is a fixed collocation. 二日間 specifies the duration (間 = 'interval / span'); without 間, 二日 would be interpreted as the 2nd of the month. The interval marker は critical here.