Welcome to the community.
It depends what is a purpose of your Elastic deployment.
If you want to use for internal use like monitoring own logs by using the basic license, without any charge to anyone it's free.
The license allows the free right to use, modify, create derivative works, and redistribute, with three simple limitations:
- You may not provide the products to others as a managed service
- You may not circumvent the license key functionality or remove/obscure features protected by license keys
- You may not remove or obscure any licensing, copyright, or other notices
Check FAQ or the software licensing FAQ and features per the subscription model. Also check the discussion.