strip_tags("Hello

world

This might work

This is removing the tags but if i use Hello then hello should appear in bold but it is not happening.

Are you using {!! ... !!} tags in your blade templates as the standard {{ ... }} tags are automatically passed through htmlspecialchars?

it would really help if you did not keep trying to post html in the forum

use backticks around your html

Like @NasirNobin said just use a getter setter or a helper function to strip tags:

    public static function fixStr($rvalue)
    {
        $rvalue = empty($rvalue) && !is_numeric($rvalue) ? NULL : trim(strip_tags($rvalue));
        return $rvalue;
    }

Note I get the two confused, accessor, mutator. I just use the terms getter and setter.

But in one part you say:

How to remove html tags

Another part:

change my string to show from Hello to hello in view buy escaping HTML tags by defining an accessor.

If all you are doing is making a word lower case you can do that direct:

$whatever = strtolower($whatever);

But yes you can make an accessor if you wish to do that.