The Sun outputs several different kinds of things.
Electromagnetic radiation
The Sun is (partially) a black-body radiator at a temperature of near 6000 K, and therefore emits all sorts of electromagnetic energy, including UV and X rays.
UV is stopped in the upper atmosphere. X rays are absorbed by the whole atmosphere, and are pretty weak anyway.
The Sun's EM activity in terms of harsh radiation increases greatly if there's a solar flare blowing up. Even then, we're pretty safe on Earth.
High energy particles
The solar wind is basically a flux of particles (nuclei of hydrogen, etc) shooting out of the Sun at pretty high energies. These are charged particles. When approaching the Earth, the Earth's magnetic field for the most part deflects them. If you're on Earth, you're safe. Even in space, the flux is not very great; you'd be safe inside a spacecraft.
However, during a solar flare, the flux of particles increases greatly. The Earth is safe, but an astronaut en route to Mars would be in a pretty unsafe situation.
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