First of all, there is nothing wrong with PHP language. Two mistakes:
1.
echo "here:"+$bandY+$bandM+$bandC+$bandK+$comment;
should be
echo "here:".$bandY.$bandM.$bandC.$bandK.$comment;
in php, dot '.' is used to concatenate strings, '+' used in javascript for this purpose.
2. The following comment
should be
<!-- there's some javascript that I'm not sure if I'm going to use yet here -->
See that you are learning hard. Good effort.