If a clutch begins slipping on a car or truck then it's an indication that the clutch needs replaced before it leads to a breakdown.
It's not dangerous to actually drive with a slipping clutch because I've done it myself years ago when I was poor and didn't have the money to get the clutch in an old car replaced on a cheap car I was driving back and forth to work.
Luckily I only had about 10 miles each way to drive to my job with the clutch slipping so it wasn't too bad of a problem.
I drove the car with the clutch slipping until I scrapped the car after I got the money to get a better car.
However I would not drive too far in a car or truck with the clutch slipping because it can lead you stranded because eventually the clutch will fail completely.
If the car is not worth fixing then driving with the clutch slipping some is okay but if the car has some value to it then I would get the clutch fixed as soon as possible.