What could we harvest from stars if the technology was available?
The actual composition of stars is actually quite simple. Although we often consider stars to be wildly complex and infinitely powerful, most stars are simply made up of a large portion of gas, oxygen, carbon, nickel and iron. Our sun is mostly made up of materials that we can find readily on earth. There's actually a little bit of Stardust in all of us.
If we have the technology available for harvesting resources from the sun one of the first targets that we would likely seek is harvesting energy. There have been a number of attempts to improve energy harvest such as with devices like the Dyson Ball, improved solar cells and more. Finding new ways that we could harvest more energy from the sun could make our current renewable resources much more efficient and it could ensure that we can continue to power our world well into the future.
One of the largest resources that we can harvest from our closest star is hydrogen. Around 70% of our son is made up of hydrogen and this is a gas that we are widely dependant on. Hydrogen is still readily available on earth but we could potentially harvest hydrogen from the sun in massive quantities to power vehicles, power space exploration and more.
Other resources like neon, iron, silicon, sulfur and magnesium could be potentially harvested if we had the technology. These are also resources that are not in advance scarcity on earth. Other stars throughout our universe are made up of different gases and materials. If you the power to travel to new worlds we could potentially unlock the ability to harvest gases and materials that are far scarcer than items we would find in our solar system.