When you have a car with a manual transmission and the clutch begins slipping it's a sign that the clutch is wearing out and needs to be replaced soon.
If you continue to drive the car with the clutch slipping it can do more damage to the clutch and transmission and cause you to completely lose the clutch where you won't be able to shift the car at all and be able to drive it and you could be stranded.
You need to have the clutch fixed as soon as possible and avoid driving the car with the worn out clutch for very long.
Get the clutch fixed as soon as possible to avoid damaging the clutch system further and the cars transmission further.
So you can drive the car for awhile with the clutch slipping but avoid driving the car too far until you get the slipping clutch fixed.