Is basal cell skin cancer dangerous? I’ve heard it doesn’t spread, so do I need to worry about getting it?

See below. Basal cell cancer almost never metastasizes, but untreated, will continue to grow. It is easily treated at an early stage, but if its growth involves vital structures, treatment can be disfiguring. In extreme cases, it can cause death. The moral of the story: as cancers go, it is not bad, but as for all cancers, it should be treated appropriately.
No. People do not die from basal cell skin cancers. But delay in treatment allows it to destroy local tissues. You could lose your nose or your ear. You could get a giant ulcer. If you have a suspicious skin lesion see a dermatologist. Wear a hat and don't get burned when you are out in your yacht.
Yes. Some folks choose to neglect basal cell carcinomas because they seldom spread to distant locations. Instead, give them the time and they destroy an eyeball or eat directly through the skull and into the brain. Please get yours taken care of.
Not usually. Compared to melanoma it is not as dangerous of a skin cancer. It does need to be treated to prevent progression. It does have the possibility to spread, but not as common as melanoma.