how come stars burn at space if there is no oxygen in space?
Stars do not "burn" in the same way as a fire.
Stars "burn" thanks to fusion processes, see e.g.
and also the sun?
Yes. The sun is our local star.
oooh fusion yess.. whats that i cant understand the link above
Nuclear fusion is the process of combining light nuclei, like hydrogen, into heavier nuclei, like helium. The process releases energy.
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