Preventing Earth's Destruction

Our sun will get hotter over time and in about 600 million to 700 million years the conditions on earth won’t allow for photosynthesis. All the oceans will boil away a little while later. The earth will be a dead rock by the time the sun gets within a few billion years of turning into a red giant, at which point the sun will enlarge enough to engulf our planet. Europa might be nice, sunny, and perhaps habitable by then. Given the lead time that humanity has (more than 500 million years) humanity could perhaps engineer the Earth away from the heat (if humanity even survives by that time) or maybe mine the sun to prevent it from becoming a red giant in the first place, followed by moving the sun itself to a more friendly long-term location.