Adding videos from YouTube to your blogger blog is fairly easy and requires few steps to be followed.
Find your favorite video that you want to put on your blogger blog. Go to YouTube and find your video
Now that you have made up your mind , click " Share " button beneath the video. Now click embed this video button. Choose the video dimensions that you want on your blog. For making custom dimensions that are not available in the share option watch the tutorial below.
Now that you have chosen your dimensions for video to be embed on your blogger blog, copy the link. Now sign in your blogger and go to design and add a new html/java script widget. ( This is only if you want you video not to be inside the post.)
( For embedding inside blogger post read this article : How To Add YouTube Videos Inside Blogger Post )
Now that you have opened html/java script widget , copy your link in it . Done! Hope that was easy. Comment for any further questions