If an alien biologist researched the environment where human beings evolved on Earth, and you asked him if non-technical humans with only the materials available in their local environment could survive above the Arctic Circle, he would probably laugh at you.

ER is right that human exploration and colonization has ALWAYS been dangerous.

Humans will figure out ways to survive anyplace that they need to or want to.

The simplest way to avoid radiation is to put enough mass between you and it, which for most space colonists on planetary surfaces or on asteroids just means finding caves or digging holes. More advanced techniques can use magnetic fields to deflect the charged particles.

Remember that low Earth orbit is (relatively) benign, being sheltered by Earth's magnetic field, and low Earth orbit is halfway to anywhere.