Magento 2.4 version have given feature to add table using declarative schema.

Module name : Magemonkeys_Core

We need to create db_schema.xml file in the app/code/Magemonkeys/Core/etc/  folder

<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Setup/Declaration/Schema/etc/schema.xsd">
   <table name="customtable" resource="default" engine="innodb" comment="Custom table">
      <column xsi:type="smallint" name="id" unsigned="false" nullable="false" identity="true" comment="ID" />
      <column xsi:type="varchar" name="name" nullable="false" length="20" comment="Name" />
      <column xsi:type="varchar" name="email" nullable="false" length="20" comment="Email" />
      <constraint xsi:type="primary" referenceId="PRIMARY">
         <column name="id" />
      </constraint>
   </table>
</schema>

After that, we need to generate db white list schema json

For that, we need to run command as per below

php bin/magento setup:db-declaration:generate-whitelist --module-name=Magemonkeys_Core

After that we need to run setup:upgrade and cache:flush command

That’s it.