Ronald Reagan was the leader who was given the credit for ending the cold war. He did many things during the cold war as well that led up to being given the most credit. For example, Reagan had the berlin wall taken down. There's are many instances where he has done important things.
If you need more in depth details here are a few links.
https://en.wikipedia.org/wiki/Tear_down_this_wall!
https://en.wikipedia.org/wiki/Foreign_policy_of_the_Ronald_Reagan_administration#:~:text=The%20Reagan%20Administration%20implemented%20a,commodities%20on%20the%20world%20market%3B
In the ending of the cold war, Reagan and Gorbachev also signed a treaty getting rid of certain missiles.
https://en.wikipedia.org/wiki/Intermediate-Range_Nuclear_Forces_Treaty#:~:text=US%20President%20Ronald%20Reagan%20and,treaty%20on%208%20December%201987.&text=The%20treaty%20did%20not%20apply,of%20on%2Dsite%20verification%20inspections.
Keep in mind that even though this is a 4 paragraph essay, the paragraphs do not have to be long and wordy. Don't over think it, don't over stress it. I hope this helps.
