How to add a picture from my pc, in a html code?
Have a look at this post
You'll need to upload your image to a image hosting service like Imgur, Google drive, or Flickr. I recommend the last two services for privacy. You'll need to register an account for Google drive and Flickr. Imgur does not require an account and it is a quicker proccess.
Then, once your image is uploaded, simply right click the image and click 'copy image address' (the wording of this option can change for different browsers), now you can paste it into codeacademy.
**While it is possible to link to images directly from your PC (when creating html pages on your own hard drive), they will only be visible to you.