Vertical line in iphone se

Truly can't see what you see from the screenshot your posted. Why would you be concerned about liquid damage? Did the phone come in contact with liquids? If it did, liquids can certainly damage an iPhone, and liquid damage cannot be fixed, nor is it covered under iPhone warranty.

Since you have a concern though, schedule an appointment at your Apple Store Genius Bar for evaluation and options.

I can see that. As I suggested, schedule an appointment at your Apple Store Genius Bar for evaluations. I also see the phone screen is cracked, thus there is obvious damage. At a minimum, you'll need to pay Apple to replace the screen on your phone. But also be prepared that if the phone is determined to have been subjected to liquids, you'll be buying a new phone.