This is the safest and easiest method. It requires no downloads and won't hog your limited system resources.
You may have come across suggestions online that clicking or using a bit.ly link can somehow "fix" the YouTube app on your Android 6 device. It's important to address this clearly: . bit.ly youtube android 6
When dealing with shortened links (Bit.ly) on older operating systems like Android 6.0, caution is advised. Because shortened links hide the original URL, they can sometimes be used to disguise malicious sites. This is the safest and easiest method