not bold or linked

What network are you talking about? Most networks do not allow HTML at all.

facebook i m trying to post it to facebook and the above code is the message format

Have you ever saw a bolded or linked text on Facebook anywhere?

Facebook does not allow any kind of text formatiing or HTML.

when we in default format the title is bold blue which on clicking takes to the url …i m trying to get tht effect

plus i want the clickhere to have the link

Again. Facebook does not allow any kind of text formatiing or HTML.

You can’t make text on Facebook bold, italic, underlined, etc..
You can’t change text color.
You can’t make link as “Click Here”.
You can’t insert images in the middle of the text.

None of that is possible in any way anywhere on Facebook.

but then how come in the default format the title is bold in blue and on clicking it it redirects to the page url

e.g

in Text Post with “attached” blogpost and link attachment type as Attach your blogpost

u have the thumbnail of featured image with the title in blur next to it and the text below

This is NOT something you can control. This is the standard way how the Facebook attaches the links.

in the plugin – theres an option Text Post with “attached” blogpost <– (What’s the difference?)
Link attachment type: Share a link to your blogpost .. or .. Attach your blogpost

is there a way to remove the thumbnail from this?

I beleive if you choose not to let Facebook decide your info, and select “No Image” it will post without it. It could keep the box for thumbnail though.