do i need a special tool to open the SIM Card tray on Apple iPhone 12?

A paper clip works.

See the following from Remove or switch the SIM card in your iPhone - Apple Support

Find your model below to locate the SIM tray. To pop open the SIM tray, insert a paper clip or a SIM-eject tool into the hole beside the tray. Push in, towards your iPhone, but don’t force it. If you're having difficulty ejecting the SIM tray, take your device to your carrier or an Apple Store for help.