Below is the Trigger , trying to write Test class for it but i don't have any hands on Experience Can anyone help me with this 

public class NotifyRegionalSalesTeam_cls {
    
    public static void notifyRegionalSalesLeaderOnContactType(List<Independent_Dealer_Review__c> newDealerReviewList,Map<id,Independent_Dealer_Review__c> oldDealerReviewMap,user usr,boolean isInsert){
       List<Messaging.singleEmailMessage> mails = new List<Messaging.SingleEmailMessage>();
       Messaging.singleEmailMessage mail = new Messaging.singleEmailMessage();                                                         
       Map<id,List<Independent_Dealer_Review__c>> accToDealerReviewsMap = new Map<id,List<Independent_Dealer_Review__c>>();
       boolean firstRun = false;
       integer count = 0;
       integer mapSize = 0;
       EmailTemplate template = [select id,name from Emailtemplate where name = 'Ind. Dealer Contact Type as Phone vf'];

         for(Independent_Dealer_Review__c temp:newDealerReviewList){
             if(temp.Ind_Dealer_Contact_Type__c == 'Phone' && isInsert){
              if(accToDealerReviewsMap.containsKey(temp.Account__c)){
                  accToDealerReviewsMap.get(temp.Account__c).add(temp);
              }else{
                  accToDealerReviewsMap.put(temp.Account__c,new List<Independent_Dealer_Review__c> {temp});
                } 
                 mapSize++;
             }
             if(!isInsert){
                 count ++;
                 if((temp.Ind_Dealer_Contact_Type__c == 'Phone' && count == 1 && oldDealerReviewMap.get(temp.id).Ind_Dealer_Contact_Type__c != 'Phone') || (temp.Ind_Dealer_Contact_Type__c == 'Phone' && count == 2)){
              if(accToDealerReviewsMap.containsKey(temp.Account__c)){
                  accToDealerReviewsMap.get(temp.Account__c).add(temp);
              }else{
                  accToDealerReviewsMap.put(temp.Account__c,new List<Independent_Dealer_Review__c> {temp});
                } 
                 mapSize++;
              }
             }
             system.debug('***accToDealerReviewsMap**' +accToDealerReviewsMap);
            if(mapSize == 2 && firstRun == false){
                firstRun = true;
               list<string> toAddresses = new List<string>();
                if(temp.Regional_Sales_Leader__c != null){
                    toAddresses.add(temp.Regional_Manger_Email__c);
                }
                
           if(toAddresses.size() > 0){
               mail.settargetObjectid(usr.id);
               mail.setTreatTargetObjectAsRecipient(false);
               mail.setwhatid(temp.id);
               mail.settoAddresses(toAddresses);
               mail.setsaveAsActivity(false);
               mail.settemplateId(template.id);
               mails.add(mail);  
             }               
           }
         }   
        
        if(mails.size() > 0){
           system.debug('sending Email');
            messaging.sendEmail(mails);           
        }
      }
    
    public static void notifyRegionalSalesManageronRSLCheck(List<Independent_Dealer_Review__c> newDealerReviewList,Map<id,Independent_Dealer_Review__c> oldDealerReviewMap,user usr,boolean isInsert){
       List<Messaging.singleEmailMessage> mails = new List<Messaging.SingleEmailMessage>();
       Messaging.singleEmailMessage mail = new Messaging.singleEmailMessage();                                                         
       Map<id,List<Independent_Dealer_Review__c>> accToDealerReviewsMap = new Map<id,List<Independent_Dealer_Review__c>>();
       boolean firstRun = false;
       integer count = 0;
       integer mapSize = 0;
       EmailTemplate template = [select id,name from Emailtemplate where name = 'Independent Dealer Review RSL Checked vf'];

         for(Independent_Dealer_Review__c temp:newDealerReviewList){
             if(temp.Escalate_to_RSD__c   == TRUE && isInsert){
              if(accToDealerReviewsMap.containsKey(temp.Account__c)){
                  accToDealerReviewsMap.get(temp.Account__c).add(temp);
              }else{
                  accToDealerReviewsMap.put(temp.Account__c,new List<Independent_Dealer_Review__c> {temp});
                } 
                 mapSize++;
             }
             if(!isInsert){
                 count ++;
                 if((temp.Escalate_to_RSD__c== TRUE && count == 1 && oldDealerReviewMap.get(temp.id).Escalate_to_RSD__c   != TRUE) || (temp.Escalate_to_RSD__c == TRUE && count == 2)){
              if(accToDealerReviewsMap.containsKey(temp.Account__c)){
                  accToDealerReviewsMap.get(temp.Account__c).add(temp);
              }else{
                  accToDealerReviewsMap.put(temp.Account__c,new List<Independent_Dealer_Review__c> {temp});
                } 
                 mapSize++;
              }
             }
             system.debug('***accToDealerReviewsMap**' +accToDealerReviewsMap);
            if(mapSize == 2 && firstRun == false){
                firstRun = true;
               list<string> toAddresses = new List<string>();
                if(temp.Regional_Sales_Leader__c != null){
                    toAddresses.add(temp.Regional_Manger_Email__c);
                }
                
           if(toAddresses.size() > 0){
               mail.settargetObjectid(usr.id);
               mail.setTreatTargetObjectAsRecipient(false);
               mail.setwhatid(temp.id);
               mail.settoAddresses(toAddresses);
               mail.setsaveAsActivity(false);
               mail.settemplateId(template.id);
               mails.add(mail);  
             }               
           }
         }   
        
        if(mails.size() > 0){
           system.debug('sending Email');
            messaging.sendEmail(mails);           
        }
      }

}