ANA airlines question

I plan to use the LTT backpack (https://www.lttstore.com/products/backpack) for a japan trip. Would it be counted as a backpack or a carry on? I heard ANA allows 2 check in + 1 backpack + 1 carry on

This is the size listed for a carry on:

Total linear dimensions (length + width + height) cannot exceed 45 in. (115 cm)

The dimensions of each side cannot exceed 22 x 16 x 10 in. (55 cm x 40 cm x 25 cm)

LTT backpack: Height: 18.75" / 47.63cm (excluding handle)
Width: 13" / 33.02cm (excluding straps)
Depth: 11.5" / 29.21cm

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I apologize for the stupid question, this is my first international trip for vacation.