Google designed the Pixel Watch 4 to be serviceable (or repairable) and an iFixit teardown today shows how easy it is to do so.
To remove the SIM card from your iPhone, you'll need to eject the SIM card tray with a special tool or paperclip.
You can remove the SIM card from your Samsung Galaxy S10 using the SIM removal tool that came with your phone, or a very thin paperclip.