(pics)Help! waterneck coolant line where does this connect to or weld it sealed?

I’ve seen pics on some blocks where they cut and weld this opening sealed. In an lsvtec (b18a1 bottom/ b17a head) does this need to be sealed? Otherwise where does this connect to?

Here’s a pic of it:

red x

hit refresh and it showed up for me. but i have no idea about your question. sorry