vinid, why do you say that you can't have "some vacations" please? I am English and I could easily say that "after the Covid 19 lockdown is over I will have some vacations (or holidays)". What I think is wrong with this phrase is that DL only translate it as "I will have a holiday", when surely the "algumas" should stipulate it being translated as "some vacations" not "a vacation"?
holiday - feriado / vacation - férias
Here in Brazil it would be like this; at least that's how I see it. Vacation would be a longer break while holiday would be just a day off (or 2, 3...). But I don't really know if there's a difference in english.
Holiday - A day free from work that one may spend at leisure, especially a day on which custom or the law dictates a halting of general business activity to commemorate or celebrate a particular event.
Vacation - A period of time devoted to pleasure, rest, or relaxation, especially one with pay granted to an employee.
Isn't that Spanish rather than English? I guess you mean vacations.
This vacation(s)/holiday(s) business is not easy to sort out because what sounds good to one English speaker doesn't necessarily sound good to another (particularly when you take into account national differences like US vs UK usage). For me, either "vacation" or "holidays" sound best - please don't ask me to justify that :-)