What do you do if I spilled soda on my iPhone charging port?

I suspect soda in your charging port will not be a good thing. It is a highly corrosive liquid and liquid damage can't be fixed. You can schedule an appointment at your Apple Store Genius Bar, but Apple likely won't be able to do much for you and yes, you may need to purchase a new phone.

Whatever you do, DON'T attempt to charge the phone. I'd power it off until you can have it looked at.

I'm sure you did panic. Soda and iPhone are mortal enemies, as are all liquids, but sugary liquids even more so. You need to have your phone checked by Apple.

This support page may be helpful: About splash, water, and dust resistance of iPhone 7 and later - Apple Support

Not to mention that when it dries, it leaves behind a sugary syrup residue.

Johnathan Burger wrote:

Not to mention that when it dries, it leaves behind a sugary syrup residue.

That too.........