Uploading certain programs on a computer could cost money. It depends what you are uploading and where you are getting it from. Many uploads are free.

No

Browsing is just looking i.e. neither uploading nor downloading

Uploading is puttings things from a computer on to a site

Downloading is from a site to a computer

somewhere you can change the color of your eyes by uploading a photo

Uploading is the process of transferring a file or files from a local machine onto a remote machines.

Of course not. Because the process is uploading, not syncing...