Bab 1865: The Most Important Attributes.

His three stats appear all the time at the edge of his vision. The three resources show themselves as bars that he can focus on at any time to see more information about them.

They have different colors that represent whether they are for health, focus, or stamina. He just needs to focus on them to see what their exact value is. But just by looking at the length of the bar, he can tell how low he is running on them. 

As for his attributes, he needs to call out his stat page to check them out. Then they would appear in front of him on a holographic panel together with his stats. It seems Ragna could also see them.

Ragnar could indeed see them. It pointed out to him, "The most important attribute is the MANA attribute. MANA is an unlimited external resource. How much of it you can use and how great of a power you can acquire from each use are dependent on you. Specifically your Spirit and Mana attributes."