No, you do not need your own Google Merchant Center account to get started with Google Free Listings or a Smart Shopping campaign.
If you do not already have a Google Merchant Center account to import into your Kliken campaigns, Kliken will automatically create and set up one for you. As part of this process, your website must be verified to confirm where your products are hosted in your online store.
Important Considerations:
Website Claiming Limitation: A website can only be claimed in one Google Merchant Center account at a time. If you have already verified your website in an existing Google Merchant Center account, you must import that account into Kliken instead of creating a new one.
Creating an External Google Merchant Center Account: If you later decide that you need a separate Google Merchant Center account outside of Kliken, you should create a new account directly through Google Merchant Center.