Hello, thank you for getting in touch and for your support!
In order to create a shader for particle effects, you'll need to use our Particle
Shader Template:

We also provide a sample that shows how you can build a simple effect using these template, which you can find here:
AmplifyShaderEditor \ Examples \ Official \ TemplateExamples \ Particles \ HeatHaze
Please let me know if this helps, thanks!