At least one way to look at this is from generally agreed upon "world issues" [1], since the subject is "make the world a better place." Survey among the 8,000,000,000, and a large percent would agree that many are issues.
[1] https://en.wikipedia.org/wiki/List_of_global_issues
Of those, ones that I personally think are actually meaningful, and less subject to opinion, tend to be mostly "Maslow's hierarchy of needs" [2] as a starting point for evaluation.
[2] https://en.wikipedia.org/wiki/Maslow%27s_hierarchy_of_needs
Basic needs that must be met for survival, and which significant portions of the population in many areas have difficulties with.
- air, water, food, heat, clothes, shelter, and sleep
Security needs to not be in a constant state of suffering and worry
- health security, personal security, emotional security, financial security
Of those listed on the article for "global issues" that then speak to many of those.
- poverty alleviation, malnutrition and lack of food / water access, waste (consumer waste, food waste, waste disposal, landfills, recycling, water pollution, air pollution), human rights (exploitation, abuse, enslavement, torture).
Of the climate change stuff, there's a lot that's unfortunately too easy to argue about. However, there's a few that maybe meet standards where large numbers would agree.
- desertification, ecosystem collapses, large scale biome losses / deforestation
Of a lot of the rest, unfortunately (also personal opinion) many are just too easy to argue about, and heavily dependent on where you're from, perspective, and relation to a group or area.
- terrorism, migration, democracy, big data (?), carbon, inclusiveness
Quite a few of the rest, I agree they're issues, just whether they reach the level of global critical / catastrophic issues? Many also seem to be issues that have recently gotten everybody's attention, yet there is suspiciously little mention of things like "lack of shelter / clothing access", "lack of heat sources", "sleep deprivation", "basic needs health care access"
Used to work in the government, and they had a Likelihood / Consequence Risk Matrix [3] for evaluating some of the flight and mission hazards. Most of the stuff listed personally rates somewhere up on the (Moderate, High, Very High) Likelihood / (Moderate, High, Very High) Consequence. Stuff that would almost always be Yellow to Red, and require mitigation actions or attempts. Many of the ones that don't meet my criteria tend to be too easy to fight about the Likelihood or the Consequence results. "Is 'Big Data for Sustainable Development' a near term Moderate+ likelihood / consequence?" Seems too easy to argue about to be on the United Nation's critical list of global issues.
[3] https://www.nature.com/articles/s41526-023-00305-z/figures/2
Anyways, best attempt at providing advice on "make the world a better place." Frankly, think most people's work on Earth probably does not meet the criteria.