User:Smelt93
About
Project-S is a learning resource whose lessons are devoted to mapping and the Source SDK in general.
You can find hundreds of text lessons in the https://vk.com/project_source community, and dozens of video lessons on the https://www.youtube.com/channel/UCFm85297tod5yyZJn7D1HPw channel.
An old tutorial on entities
You can download the training document HERE.
You can find all the new lessons: In the VK Community, On Youtube and on this site in the article about the Entity.