There is various methods of that.
You can use plugins, add shortcode or use
Theme Customization API.
As well as there is various methods of editing HTLM code. Either you do that from admin panel or by FTP (which is most recommended).
But most important question is:
What do you want to achieve?
You need to specified that question.
i haven’t seen i have connect with http://FTP.THE Main goal is I want to add br tag