Sample Code:

LWC HTML:

<template>  
    <div class="slds-box slds-theme_default">  
  
        <lightning-record-edit-form record-id="0013i00000362blAAA"    
                                    object-api-name="Account"    
                                    onsuccess={handleSuccess}>    
            <lightning-messages></lightning-messages>    
            <lightning-output-field field-name="Name"></lightning-output-field>    
            <lightning-input-field field-name="Industry"></lightning-input-field>    
            <lightning-input-field field-name="Description"></lightning-input-field>    
            <lightning-input-field field-name="Rating"></lightning-input-field>    
            <lightning-button class="slds-m-top_small"    
                            variant="brand"    
                            type="submit"    
                            name="update"    
                            label="Update">    
            </lightning-button>     
        </lightning-record-edit-form>   
    </div>  
</template> 

LWC JavaScript:

import { LightningElement } from 'lwc';  
  
export default class Sample extends LightningElement {  
  
    handleSuccess( event ) {    
    
        const payload = event.detail;            
        var objJSON = JSON.parse(JSON.stringify(payload));  
        alert(objJSON["fields"]["Industry"]["value"]);    
    
    }  
  
} 

LWC meta.xml:

<?xml version="1.0" encoding="UTF-8"?>  
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata">  
    <apiVersion>47.0</apiVersion>  
    <isExposed>false</isExposed>  
    <targets>  
        <target>lightning__Tab</target>  
    </targets>  
</LightningComponentBundle>  

Output: