Pass value from child lightning component to parent lightning component using Dispatch Event: LWC

Parent Lightning Component

parentComponent.html

<template>

    <lightning-card>

        <div class="slds-p-around-medium">   

            {selectedAccountId}

            <template for:each={accountsList} for:item="accountRecord" >

                <c-child-component account={accountRecord} key={accountRecord.Id} onobjectlistitemselected={handleObjectListItemSelected}></c-child-component>

            </template>

        </div>

    </lightning-card>

</template>

parentComponent.js

import { LightningElement, wire, track } from 'lwc';

import getAccountList from '@salesforce/apex/PullAccount.seacrhAccount';

export default class ParentComponent extends LightningElement {

    

    @track accountsList;

    @track error;

    searchKey = *****ACCOUNT RECORD ID*****;

    @track selectedAccountId;

    @wire(getAccountList, { accountRecordId: '$searchKey' })

    wiredAccounts({ error, data }) {

        if (data) {

            this.accountsList = data;

            this.error = undefined;

        } else if (error) {

            this.error = error;

            this.accountsList = undefined;

        }

    }

    handleKeyChange(event) {

        window.clearTimeout(this.delayTimeout);

        const searchKey = event.target.value;

        this.searchKey = searchKey;

    }

    handleObjectListItemSelected(event) {

        console.log(event.detail.recordaction+'=========='+event.detail.recordId);

    }

}

parentComponent.meta

<?xml version="1.0" encoding="UTF-8"?>

<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata">

    <apiVersion>48.0</apiVersion>

    <isExposed>true</isExposed>

    <targets>

      <target>lightning__AppPage</target>

      <target>lightning__RecordPage</target>

      <target>lightning__HomePage</target>

    </targets>

</LightningComponentBundle>

childComponent.html

<template>

    <lightning-input class="cb" type="checkbox" label="my checkbox" onchange={onChecboxChange}></lightning-input> {account.Name} {isSelected}

</template>

childComponent.js

import { LightningElement, api , track} from 'lwc';

export default class ChildComponent extends LightningElement {

    @api account;

    @track isSelected = false;

    

    onChecboxChange(event) {

        this.isSelected = event.target.checked;

        this.dispatchEvent(

            new CustomEvent('objectlistitemselected',{

                detail:  {recordId:this.account.Id, recordaction:event.target.checked}

            })

        );

    }

}

PullAccount.cls

public class PullAccount {

    @AuraEnabled(Cacheable=true)

    public static List<Account> seacrhAccount(String accountRecordId) {

        //return [SELECT Id, Name FROM Account WHERE Id =: accountRecordId];   

        return [SELECT Id, Name FROM Account LIMIT 5];        

    }

}