为什么this.id不能替换此脚本中$（selector）.html中的选择器？

I am new to this programming world and what I think seems logical is not working. I am trying to get different data sources into different divs. I have looked at all the different answers listed on this site, however the levels of answers are sometime beyond the problem that I have with script. I would love to understand why this does not work more than just getting an answer. I am new to this programming world and what I t