apex class :
public with sharing class EnrollmentFormClass {
public Contact con {get;set;}
public Contact conc {get;set;}
public Contact conct {get;set;}
public List<Contact> concAddList{get;set;}
public Account acc {get;set;}
    
public EnrollmentFormClass() {
     con  = new Contact();
     conc = new Contact();
     conct = new Contact();
     acc  = new Account();
     concAddList  = new List<Contact>();  
     //concAddList.add(con);
     }
    public void AddRow(){
        conct = new Contact();
        concAddList.add(conct);
        //concAddList.add(new Contact());
    }
public void save(){
    insert con;    
    acc.name = con.lastName;
    insert acc;
    con.AccountId = acc.Id;
    conc.AccountId = acc.Id;
    conct.AccountId = acc.Id;
    
    insert conc;
    insert conct;
    insert concAddList;
    update con;
   
    }
     
}
visualforcepage :

<apex:page controller="EnrollmentFormClass">
    <apex:form >
    <apex:pageBlock title="Opportunitiy Zone Enrollment Form">
              <apex:pageBlockSection columns="3">
              <apex:inputField value="{!con.Student_Name__c}"/>
              <apex:inputField value="{!con.School__c}"/> 
              <apex:inputField value="{!con.Date__c}"/> 
            </apex:pageBlockSection>
            <br/> 
            <br/>
                    SPARC programs are funded by United Way of Greater Atlanta. As such, we are required to report demographic, income, educational and health access information on every individual/family we serve. With the United Way belief that serving one family member serves them all, we collect general information on each member of your household. We appreciate your willingness to complete this form in its entirety so that we can continue providing free programs to the community. Thank you!
            <br/>  
            <br/> 
            <apex:pageBlockSection title="Head of Household Information:">
                <apex:inputField value="{!con.FirstName}"/>
                <apex:inputField value="{!con.LastName}"/>
                <apex:inputField value="{!con.Date_of_Birth__c}"/>
                <apex:inputField value="{!con.Gender__c}"/> 
                <apex:inputField value="{!con.Do_you_have_a_primary_medical_provider__c}"/>
                <apex:inputField value="{!con.Do_you_have_a_primary_medical_provider__c}"/>
                <apex:inputField value="{!con.Address__c}"/>
                <apex:inputField value="{!con.City__c}"/>
                <apex:inputField value="{!con.State__c}"/>
                <apex:inputField value="{!con.County__c}"/>
                <apex:inputField value="{!con.Phone__c}"/>
                <apex:inputField value="{!con.Email_Address__c}"/>
                <apex:inputField value="{!con.Preferred_Method_of_Contact_Circle_One__c}"/>
            </apex:pageBlockSection>
            <apex:pageBlocksection title="Demographic Data: (All information is confidential and is used in applying for grants to fund this program.)" columns="3">
                 <apex:inputField value="{!con.Spanish_translation_Services_Needed__c}"/>
                 <apex:inputField value="{!con.Race_Check_One__c}"/>
                 <apex:inputField value="{!con.Marital_Status_check_one__c}"/>
                 <apex:inputField value="{!con.HIGHEST_LEVEL_OF_EDUCATION_Check_one__c}"/>
                 <apex:inputField value="{!con.Employment_check_one__c}"/>
            </apex:pageBlocksection>
            <apex:pageBlocksection title="Income:" columns="3">
                <apex:inputField value="{!con.Annual_Income__c}"/> 
                <apex:inputField value="{!con.Source_of_Income__c}"/> 
                <apex:inputField value="{!con.Primary_Method_of_Transportation__c}"/>
            </apex:pageBlocksection>
            <apex:pageBlocksection title="HOUSEHOLD Information:" columns="3">
                <apex:inputField value="{!conc.Other_Adult_First_Name__c}"/>
                <apex:inputField value="{!conc.LastName}"/>
                <apex:inputField value="{!conc.Date_of_Birth__c}"/>
                <apex:inputField value="{!conc.Gender__c}"/> 
                <apex:inputField value="{!conc.Relationship_Primary_Care_Provider__c}"/>
                <apex:inputField value="{!conc.Medical_Insurance__c    }"/> 
            </apex:pageBlocksection>
                <apex:pageBlockButtons location="bottom" >
                <apex:commandButton action="{!save}" value="save"/>
            </apex:pageBlockButtons> 
            <apex:pageBlocksection title="Children (all children currently in your household, INCLUDING those participating in this program):" columns="1">
             <apex:pageBlockTable value="{!conct}" var="c">
             <apex:column headerValue="Name">
             <apex:commandButton action="{!AddRow}" value="AddRow"/>
             </apex:column>
             <apex:column headerValue="Name">
             <apex:inputfield value="{!c.LastName}"/>  
             </apex:column> 
             <apex:column headerValue="Date of Birth">
             <apex:inputfield value="{!c.Date_of_Birth__c}"/>
             </apex:column>
             <apex:column headerValue="Gender">
             <apex:inputfield value="{!c.Gender__c}"/>
             </apex:column>
             <apex:column headerValue="Relationship Primary Care Provider">
             <apex:inputfield value="{!c.Relationship_Primary_Care_Provider__c}"/>
             </apex:column>
             <apex:column headerValue="Medical Insurance">
             <apex:inputfield value="{!c.Medical_Insurance__c}"/>
             </apex:column>             
       </apex:pageBlockTable> 
       </apex:pageBlocksection>
       </apex:pageBlock>
    </apex:form>
</apex:page>