A lot of people are thinking about this question! Most scientists agree that climate change will continue to get worse. But how much worse? The damage could be lessened if humans take action to prevent more greenhouse gases from being released into the atmosphere.
Rather than focusing on individual actions, we have to create a society where it is easy to make environmentally-friendly choices. If just one person bikes instead of driving, it makes almost no difference. But if a person gets involved in local government, or contacts city officials to get them to build bike lanes, or designate bus-only traffic lanes- then sustainable transit becomes an easy option for many people- and that can help reduce greenhouse gas emissions.
It will be important for society to switch to clean and renewable energy, instead of coal and oil, which release carbon dioxide when burned. Scientists are working on making these new technologies (for example, solar panels) cheaper and more efficient. The governments of developed countries need to allocate funding to this research, and create incentives for companies to switch to clean technologies. Individuals can help by participating in research, educating others, and voting to elect officials who will prioritize clean energy.