Certified GKH Gardening Expert
Those stems from the bottom are actually a totally different plant! I notice that you also have some of the portulaca growing with the grafted moon cactus in the back!
What you can do (I wouldn't chop it in half) is take a leaf from the bottom, and set it next to the plant in the soil. It will eventually root, and grow a new shoot to become its very own plant! You can also wait until it send up a pup beside it. They will be able to be separated off and rooted separately as well.
The reason that your Echeveria is getting so tall may be a lack of light. These plants are suited for full sun. This means at least 8 hours of direct sun per day. The more the better.
There are many types of Echeveria. They all have very similar care. This article will help: https://www.gardeningknowhow.com/ornamental/cacti-succulents/echeveria/caring-for-echeveria-plants.htm