I can’t see reset option on my phone

I'm not sure what you mean by reset, but The first (and simplest) thing to try if something isn’t working right is to restart your iPhone. If necessary (device not responding), try a forced restart. Both methods can be found here:

Restart your iPhone - Apple Support

If you want to reset the iPhone to factory settings, then see:

How to erase your iPhone, iPad, or iPod touch - Apple Support