Remote code execution

Any one tell me how i learn remote code execution i search on youtube and google but not get any good stuff of any video or course link will you expert guyz help me how i learn some good techniques 2019
Big stuff for remote code execution

Remote Code Execution isn’t as much a vulnerability type as it is a type of impact that a vulnerability can have. There’s tons of ways to achieve RCE - you have to be creative and think outside the box.

In webapps, RCE is commonly achieved through OS Command Injection, Server-Side Template Injection, malicious file upload, default admin credentials, public Jenkins instances etc.

Will u tell me how u think outside the box