SIM card free I phone

On iPhone 12 models, iPhone 11 models, iPhone XS, iPhone XS Max, and iPhone XR, you can use a physical nano-SIM for a cellular plan and an eSIM for one or more other cellular plans. If you don't have a nano-SIM and your carrier supports it, an eSIM can serve as your only cellular plan. The eSIM provided by your carrier is stored digitally in your iPhone.

Extracted from the section "Set up your cellular plan with eSIM" in this support article:--> Using Dual SIM with an eSIM - Apple Support

Regards

Giulio

iPhone 12 Pro Max supports eSIM. If EE also offers eSIM then you can order it from EE.

eSIM is, as you say, not a physical SIM card that sits in the SIM card drawer, but a built-in chip in your iPhone. It may differ from carrier to carrier. But with my carrier you order an eSIM, you also get an email with a QR code you scan with your iPhone, you also enter a PIN code which was also included in the email, and then you are connected to Cellular. Really convinient.

You can read more about eSIM here:

About eSIM on iPhone - Apple Support