This video goes through how to do parallax scrolling for infinite runners/endless runners in Unity with just 1 component. The principals also apply to Unity3d.
Links:
Link to code on GitHub:
https://github.com/WalfosDev/Infinite...
Other video for parallax scrolling in normal games:
(video has not been made yet, will be published by 17th of April 2021)
Timestamps:
00:00:00 - Final Product of tutorial
00:00:16 - Introduction
00:00:57 - How this method works
00:01:44 - Setting up the scene
00:03:21 - Coding the component
00:05:21 - Setting up the component
00:07:36 - Conclusion