Answer: The first paragraph of your essay should establish the issue, provide relevant background information to comprehend your argument, outline the evidence you will present, and state your thesis.
For example, the following introductory paragraph states these points:-
As online learning becomes more common and more and more resources are converted to digital form, some people have suggested that public libraries should be shut down and, in their place, everyone should be given an iPad with an e-reader subscription.
(the extract is taken from the website blog. prepscholar - u can search argumentative essay examples, and it will show up)
1. Background information (online learning becoming popular)
2. Opinion of people (some people suggesting)
3. Establishing the issue (public libraries should be shut down, and replaced with e-reader subscriptions)
Hope it helps!