I am new to development and need help to pass test class code coverage for my controller extension. It is currently only at 63% coverage.

Controller Extension:

public class IVExtension {
public String sortOrder = 'Parameter__c ';
public Interview__c i { get; set; }
public List<Interview_Questions__c> getq(){
    List<Interview_Questions__c> results = Database.query(
        'SELECT Id, Parameter__c , ECA_Rating__c, Response_Notes__c, Question__c ' +
        'FROM Interview_Questions__c ' +
        'ORDER BY Parameter__c ASC '
    );
    return results; }

public ApexPages.StandardController sc;
public IVExtension(ApexPages.StandardController sc) {
    i = (Interview__c)sc.getRecord();
}

public PageReference saveRecord() {
update i.Interview_Questions__r;
return null;
}
}

Test Class:

@isTest
public class testIVExtension{

    testmethod static void testcondition0(){
        test.startTest();
        try{
              Interview__c i = new Interview__c (Job_Applicant__c = 'a0D3a00000NxusC');
              insert i;
              
            Interview_Questions__c q = new Interview_Questions__c(Interview_Parameter__c = 'a2Q3a000001QPcI',Interview__c = i.id,
            ECA_Rating__c = '1',Response_Notes__c = 'test',Question__c = 'test');
            insert q;
              
         ApexPages.StandardController sc = new ApexPages.standardController(i);
            IVExtension IE = new IVExtension(sc);
            IE.saveRecord();
        } catch (Exception e)
        {
            system.assert(e!=null);
        }
        test.stopTest();
    }
    testmethod static void testcondition1(){
        test.startTest();
        try{
          List<Interview_Questions__c> results = Database.query(
        'SELECT Id, Parameter__c , ECA_Rating__c, Response_Notes__c, Question__c ' +
        'FROM Interview_Questions__c ' +
        'ORDER BY Parameter__c ASC '
    );
        } catch (Exception e)
        {
            system.assert(e!=null);
        }
        test.stopTest();
    }
}

You can probably tell by now that I only understand half of what I'm doing...