Is there any ASCII character for <br>?

& is a character; & is a HTML character entity for that character.

<br> is an element. Elements don't get character entities.

In contrast to many answers here, \n or 
 are not equivalent to <br>. The former denotes a line break in text documents. The latter is intended to denote a line break in HTML documents and is doing that by virtue of its default CSS:

br:before { content: "\A"; white-space: pre-line }

A textual line break can be rendered as an HTML line break or can be treated as whitespace, depending on the CSS white-space property.

You may be looking for the special HTML character, 
 .

You can use this to get a line break, and it can be inserted immediately following the last character in the current line. One place this is especially useful is if you want to include multiple lines in a list within a title or alt label.