Look here at this BBC website to learn the difference between a discursive and a persuasive essay.

https://www.bbc.co.uk/bitesize/guides/zpdwwmn/revision/1

You can find for and against arguments for a variety of topics on these websites:

Debatabase:

https://idebate.org/debatabase

ProCon.org

https://www.procon.org/

Debatewise.org

https://debatewise.org/debate-categories/

Debate.org

https://www.debate.org/