For a contact edit form, you will need to provide the ID of the record that needs updating. The following example shows how to use the RecordEditForm component to edit a contact record:

<aura:component implements="force:hasRecordId,flexipage:availableForRecordHome">
    <div class="slds-p-bottom_large slds-p-left_large" style="width:500px">
 <Lightning:recordEditForm aura:id="recordViewForm" 
                                     recordId="{!v.recordId}"
                                     recordTypeId="012R00000000000000"
                                     objectApiName="Contact">
            <Lightning:messages />
            <Lightning:inputField fieldName="FirstName" />
            <Lightning:inputField fieldName="LastName" />
            <Lightning:inputField fieldName="Birthdate" />
            <Lightning:inputField fieldName="Phone" />
            <!--Picklist-->
            <Lightning:inputField fieldName="Level__c" />
             <Lightning:inputField fieldName="LeadSource" />
    <Lightning:inputField fieldName="Level__c" />
            <Lightning:button aura:id="submit" type="submit" label="Update record" class="slds-m-top_medium" />
            </Lightning:recordEditForm>
    </div> 
</aura:component>