What does it mean? 'I live at 50 Main Street.'
Does it mean I live in the 50th alley on Main Street? Or it means the number/plaque of my house/apartment building is 50 and it is on Main Street?
We don't use "plaque of my house". It's either house number, the building number or the apartment number. The latter is the least likely.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.