Sample Code:

CMP:

<aura:component implements="force:appHostable" controller="SampleAuraController">
    <lightning:card>
        <lightning:recordEditForm aura:id="recordEditForm" objectApiName="Lead" onsubmit="{!c.doSubmit}">
            <lightning:messages />
            <lightning:inputField fieldName="FirstName" />
            <lightning:inputField fieldName="LastName" />
            <lightning:inputField fieldName="Email" />
            <lightning:inputField fieldName="Phone" />
            <lightning:inputField fieldName="Company" />
            <div id="recaptchaCheckbox"></div>
            <br/>
            <lightning:button aura:id="myButton" label="Create Lead" type="submit"/>
        </lightning:recordEditForm>
    </lightning:card>
</aura:component>

JS:

({
    
    doSubmit: function ( component, event, helper ) {
        
        console.log( 'Inside Submit' );
        event.preventDefault();
        let fields = event.getParam( 'fields' );
        fields = Object.assign( { 'sobjectType': 'Lead' }, fields );
        console.log( 'Fields are ' + JSON.stringify( fields ) );
        let action = component.get( "c.insertRecord" );
        action.setParams( {            
            record: fields
            
        } );        
        action.setCallback( this, function( response ) {
            
            document.dispatchEvent(new Event( "grecaptchaReset" ) );
            let myButton = component.find( "myButton" );
            myButton.set( 'v.disabled', true );            
            let state = response.getState();
            
            if ( state === "SUCCESS" ) {
                
                let result = response.getReturnValue();
                console.log( 'Result is ' + JSON.stringify( result ) );
                
                if ( result === 'Success' ) {
                    
                    let showToast = $A.get( "e.force:showToast" );
                    showToast.setParams( {
                        
                        title : 'Lead Creation',
                        message : 'Lead Submitted Sucessfully.' ,
                        type : 'success',
                        mode : 'dismissible'
                        
                    } );
                    showToast.fire();
                    
                }
                
            } else {
                
                let errors = response.getError();
                if ( errors ) {
                    
                    console.log( errors[ 0 ] );
                    
                }
                    
                let showToast = $A.get( "e.force:showToast" );
                showToast.setParams( {
                    
                    title : 'Lead Creation',
                    message : 'Lead is not Submitted due to some error.' ,
                    type : 'error',
                    mode : 'dismissible'
                    
                } );
                showToast.fire();
                
            }
            
        });        
        $A.enqueueAction(action);
        
    }
    
})

Apex Class:

public class SampleAuraController {
    
    @AuraEnabled
    public static String insertRecord( SObject record ) {   
        
        try {
            
            insert record;
            return 'Success';
            
        } Catch( Exception e ) {
            
            return 'Failed';
            
        }
        
    }
    
}

Output: