I can used 2 sim in I phone 15 pro max

Where are you located?

The iPhone 15 sold in the U.S. is eSIM only.

Most other countries offer models with 1 SIM and 1 eSIM

China might offer a model with 2 SIM

You can use 1 SIM and 1 eSIM.

Not possible to use 2 SIM.

The iPhone 15 sold in the UK is 1 eSIM and 1 SIM

Not possible with the iPhone 15 that you have. It only has 1 SIM slot. You need a phone with 2 SIM slots.

The iPhone 15 version that you need is only sold in China.

No.

To use two carriers in UK one of them must offer eSIM

ie Vodafone, O2, 3, EE or GiffGaff

but iPhone 13 Pro Max have 2 sim or no

No in the U.K.

Yes in China