Where is the video coming from? If you are going to host it somewhere like Youtube for free then just right click the video and select "copy embed code" and paste that into a code page, it will work right away. You will have to do some more work to get it to fit where you want but that gets you a working video and the hosting is even taken care of. Change the frame size or whatever you want.
Sample of their embed code:
<iframe width="1280" height="720" src="video URL"; frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>