Can I bring Nutella?

Can I bring Nutella in a jar - not opened to Japan?

It is also sold in Japan, but do I need to bring it from your country?

I have dietary restriction i.e. Halal... I can't ascertain that the ones sold in Japan are indeed halal certified. Hence, I am intending to bring from my country.

Yes, you can (put it in your checked luggage).
There are restrictions on (fresh) plants/seeds, and meat. Other processed foods are OK.

https://www.halalfoodinjapan.com/
I don’t see why Nutella manufactured in Japan would be any different than Nutella manufactured elsewhere, but hopefully this website helps you out.

Actually the Nutella sold in Japan is imported from Australia (not Austria!). Only the 350g little pot is sold in most supermarkets. I saw 1 kg pots at Costco for more than 1000 yens. No Ferrero/Nutella factory in Japan as far as I know.

PS: On a side note, it's mostly palm oil and a lot of sugar. People should avoid this "thing". Really.

Could probably get it at "Jupiters" - they sell imported food from around the world and the kind of thing they would stock. It's like buying vegemite - that's available too even though it's pretty niche.
But, there are certainly enough halal foods in Japan that you would not stave if you didn't have Nutella for a week.