I'm making my first Joomla website and I'm here to ask you this question: since every article will have to have the same format, is there a way to save it, so I don't have to remake it everytime I write a new article?
There are several ways to save Templates for Articles.
You can save one of your Articles as a 'template' and make it unpblished so that it doesn't appear on the public view of the website. Then instead of creating a
New article you can open the 'template' article and then click on
Save as Copy to start working on a new copy of the template as your new article.
Depending on the Editor you are using for your website, some of the popular ones have Templates as a built-in feature. You need to look at what Editor you are using and then research if and how their article/content templates works.
And then there are extensions in the JED that provide article templating. A quick search brought up Regular labs Content Templater, https://docs3.regularlabs.com/contenttemplater/getting-started/introduction as possible contender but there are others.