Cant´remove embedded YouTube Video

Helo, I embedded two Youtube videos on my Homepage via the customizer function (Youtube symbol) and copy/pasted the URL (https://youtu.be/v5P_W4l-TO4 - so not the embedding code) as requested. It was taken from this video on YouTube: https://www.youtube.com/watch?v=v5P_W4l-TO4 Now I can´t remove it anymore. I can see in the embedded video in the source code, but I don´t know where to find the HTML-editor in wordpress to remove this section. I can see a lot of options under design -> theme editor. But I can´t find the html editor to remove it. Or is there maybe an easier way than to remove the embedded video than in the html editor? Thx, Jasmin