How are web parts developed in SharePoint?

in sharepoint 2013 2016

Before that, web parts are controlled by server side by adding it to web part page, in order to create web part, you have to select in which SharePoint project you want to create it and then go to the solution explorer and then select project and add new item have to be web part, give the name of the web part and then save it, it is as simple as it is.