If your iPhone isn't responding and you're not able to power it off and then on again, you can force restart it to hopefully ...

It still has a 4.7 inch screen and the home button featuring Touch ID ... With the computational power of the A15 Bionic chip, the iPhone SE’s camera is better than before.

Step 1: Press and hold the right-side button and either of the volume buttons until the Slide to power off control appears. If you're using an older iPhone, such as a first-generation iPhone SE ...

That wouldn't be a huge surprise: one of the big selling points of the iPhone SE is that there was no compromise on power ... also see the end of the home button, with a move over to Face ID ...