This means you want to manually store data in your CRM platform which tells you where the contact record originated from.
In order to do this, you will have to set up hidden fields on your landing page, and you will select which words (aka parameters) to store (i.e. “source=google” and “campaign=branded”).
Once you determine those parameters, you (or your vendor) will enter into the appropriate campaigns or ad groups.
You can double check that the UTM settings are set up correctly by clicking on "ADS & EXTENSIONS", then click and "EDIT" on an ad and then click “TEST.”
Intro to UTM parameters training here:
Keep in mind: These UTM parameters aren't quite as good as Google at tracking folks with accuracy. It's simply a piece of text that's temporarily stored in the person' browser cache when they visit the site. If they come back to the site again with new parameters sent, then the browser's cache will be overwritten with the new parameters. If they come back to the site on a different device to convert, then the browser won't push the parameters into Shopify. If they delete their cache & cookies between their first site visit and the site visit that they convert on, then Shopify also wouldn't be able to include the parameters with the sale.
Google, on the other hand, is much better at tracking folks across devices and through any accidental cache deletions or overwritings. Google has people logged in on their phones, etc. etc.
But the UTM parameters should be close enough to accurate to get a quick gauge on what percentage of traffic is coming from where! You can also compare this data with your Google Analytics account in the Source/Medium section.