@ Mohammad, to stop the pollution we may reduce the use of plastics, we can recycle it properly, we can organize a beach or river clean up, we may suggest people to avoid products containing microbeads, as well as we should support organization addressing plastic pollution.
Research shows the majority of plastic by mass is currently in the larger debris. By removing the plastic while most of it is still large, we prevent it from breaking down into dangerous microplastics.
Reduce plastic use by imposing additional fees on one time use plastic bags in the grocery store and ultimately banning them, finding more efficient ways of converting the waste to usable fuel with minimum impact on the carbon footprint, imposing additional fees on manufacturers that make non bio-degradable products, and so on.