Help! Insert one piece of codes and website crash down

You are going to have to access your hosting server via FTP and edit the file.

Thanks.
How do I know the address of my website of FTP?

Well it’s usually the same as your site, but you will have to get access credentials from your host.

Do you know what port is usually?

It is usually 21.

I just realized this was in the localhost forum. If it is on you local machine you can just edit the file and remove the code.

No, I cannot use the local machine for some reason. I use my credentials but FileZilla says:'”Command: PASS ********************
Response: 530 Login authentication failed
Error: Critical error: Could not connect to server”

Do you why?

If it is on your local machine you do not need to FTP I misunderstood. You can access your files directly on your machine wherever you installed WordPress.

I really use wp-admin to access the website so I have no idea of how to use local machine.

nellylmr –

As csloisel has mentioned, you will get the FTP login credentials from your hosting provider, that is to say, where your web site is hosted.

If this is your site, you will have that information from when you set up the hosting account. You will also have access to the hosting control panel through your hosting account login. Within that hosting control panel is a file manager which you can use as an alternative to FTP and FileZilla to upload a new copy of the function.php from a fresh copy of your theme files, or edit the changes you made (if you can recall them) ??

Thanks @csloisel and @lylechamney. The problem is been solved. The host changed the theme so I can log in to the website. I deleted the codes in Editor. Thank you!