Servers, web servers, ftp server

i've got some questions about servers used on web and i would like if You can help me please.. here there are.. i Hope you'll understand them.. Thanks.. When i want to upload a website by using an ftp client, is the server software (like apache, nginx) which manages the send files, or there is a different and dedicated server for ftp? Also, if the last one is true, this dedicated server sends the received files to the web server?

Pd: i'm sorry about muy english, it's not my native language