How to Optimize my game for Android and make it less laggy

I’ve made a unity game that’s around 25mb with no post processing, not too much objects but there’s particle efffects but they’re low quality particles, Game main quality is Medium
and It’s a bit laggy in android, How do I optimize it
I just switch it to android and build it

Run the profiler on the Android build to get an idea of where the lag is coming from first. Maybe you’ve got shaders which aren’t optimized for mobile, no idea from here.