I wanna make a mirror plz help
You can check out this example project that creates reflection on a flat surface, like a mirror:
You can fork this project and play with it to get a better understanding of how it works and how you might incorporate the code into your project.
I hope this is helpful.
I tried that it wont work
As far as I can tell, the project I have linked is working with the current release of the engine, so you will have to elaborate a little on what you mean by it ‘not working’. It is difficult for other members of the forum to provide assistance without sufficient information.
Try to keep these questions in mind when making a post as it makes it easier for others to help you:
What behavior am I trying to code? What code have I tried in order to implement this behavior? (Include this code for others to help) What behavior is my project exhibiting now? What (if any) errors is my project generating? How might others get to my project? Why do I think the code I have used is not working? (Mostly optional, but helps you troubleshoot the issue on your own)