public class test3{
 public list<string>listSelectedNames{get;set;}
 public list<Wrapperclass>wraplist{get;set;}
 public list<Wrapperclass> containslistcheck{get;set;}

  
  public test3(){
 listSelectedNames = new list<string>();
containslistcheck  = new list<Wrapperclass>(); 
 
 wraplist = new list<Wrapperclass>();
   Wrapperclass   wf = new Wrapperclass();
                  wf.selected=false;
                  wf.name ='Samsung';
                   wf.state='AndhraPradesh';
                 
    Wrapperclass   wf1 = new Wrapperclass();
                  wf1.selected=false;
                  wf1.name ='Oneplus';
                   wf1.state='Telangana';
                                  
   Wrapperclass   wf2 = new Wrapperclass();
                  wf2.selected=false;
                  wf2.name ='Lenovo';
                  wf2.state='Chennai';
                
     Wrapperclass   wf3= new Wrapperclass();
                  wf3.selected=false;
                   wf3.name ='Redmi';
                  wf3.state='AndhraPradesh';
                  
                  
                
                
          wraplist.add(wf);
          wraplist.add(wf1);
          wraplist.add(wf2);
          wraplist.add(wf3);
         
 }
 
 
   public void duplicatecheck(){
    listSelectedNames.clear();
   
    
    for(wrapperclass wrap: wraplist){
        if(wrap.selected == true){
           
            listSelectedNames.add(wrap.Name);
           
         }  
    }
    
    system.debug(listSelectedNames);
}


 //wrapper classs
    public class Wrapperclass{
       public boolean selected{get;set;}
       public string Name{get;set;}
        public string state{get;set;}
    }
  
  
}

<apex:page controller="test3">
   <apex:form >
   <apex:pageBlock >
      <apex:pageblockTable value="{!wraplist}"  var="a">
       <apex:column ><apex:inputCheckbox value="{!a.selected}"/>{!a.name}</apex:column>
        <apex:column >{!a.state}</apex:column>
       </apex:pageblockTable>
    <apex:commandButton value="OrderSelected"  reRender="one,two" action="{!duplicatecheck}"/>
       <apex:outputLabel id="two">{!listSelectedNames}</apex:outputLabel>
    </apex:pageBlock>
   </apex:form>
</apex:page>