I Lost my iPhone

See this link for help --> If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

Is your phone powered on? Does anyone in the house have a phone and can they call your phone?

If you're sure it is in the house, I would make a phone call to your lost device.

or, since you're asking:--> Use Find My iPhone on iCloud.com on your computer - Apple Support

Regards

Giulio