Bicameral legislature. Ugh. Kids, here’s all you need: It’s a goofy phrase that simply means, “half of Congress is strictly two people per state, but the other half of Congress is a proportional number of people from each state.” For that 2nd half, you can thank James Madison.
Otherwise, here’s the risk: Let’s say you have a huge state with millions of people, like California, pushing a bill to curb 15% of commercial fossil fuel output in 20 years. Meanwhile, a tiny state, like Rhode Island, pushes a bill to force every American to wear lobster hats. They would each have equal power.