Answer 1

Eze camillus Chibuike before html5 we used div tag as a container and in that we put all tags. But in html5 we can use so many tags instead of div tags i.e. header, section, article, footer.
Article is a semantic tag means it has meaning. Not like div because it has no meaning it was used because it is block element. Thats it

Answer 2

Found from google:
https://bitsofco.de/sectioning-content-in-html5/#:~:text=If%20the%20content%20within%20the,%2C%20use%20a%20.
https://www.sololearn.com/Discuss/1120784/difference-between-article-tag-and-div-tag