About <p> line feed in html-PHP

In php or in html, if the code is written as this {code ...} then, the result is 123123123 How to Use PHP to display it as {code ...} the displayed source code is still {code ...} I tried to use the nl2br function for processing, but the code becomes {code ..... in php or html

If you write the code as follows:

123123123

The displayed result is:
123123 123

How to Use PHP to display it

123123123

The displayed source code is

123123123

I tried to use the nl2br function for processing,
But the code becomes

123123
123

Solutions

Reply content:

In php or html

If you write the code as follows:

123123123

The displayed result is:
123123 123

How to Use PHP to display it

123123123

The displayed source code is

123123123

I tried to use the nl2br function for processing,
But the code becomes

123123
123

Solutions

echo <<
  
   123456123
  

End;

Source code

123456123

Maybe you should use

Label, otherwise you do not add
Html pages do not have line breaks!