Calcium
Calcium is a mineral that is found in the ground, which is how it gets into plants. In popular culture, people often think dairy is the only way to get calcium, which is not true! When cows eat the plants, the calcium is absorbed into their milk. So, we could just cut out the middleman and just eat the plants!
There are a lot of plants that have essential minerals like calcium such as dark leafy greens, broccoli, and beans. Even some plant-based milks have fortified calcium (but be sure to shake it up before pouring, because the calcium can sink to the bottom)!