Deleting "up":
* "We need to link right now." This is the most natural and common way to say it. The emphasis would likely be on "link" and "now" to convey urgency.
Deleting "it":
This phrase doesn't really make sense without "it." You'd need to add something else to make it work, like:
* "We need to link up right now. It's important!"
* "We need to link up right now. It's urgent!"
In either case, you'd pronounce it with a casual, conversational tone. You might even shorten "right now" to "right" or "now" depending on the context.
Remember, informal speech can vary greatly depending on the situation and the people involved!