No. Oppo A5s does not have the NFC support.
Yes, Oppo A5s has a dual rear camera set up. The primary rear camera has a resolution of 13MP while the secondary rear camera is of 2MP resolution.
No. Oppo A5s does not have the 5G network support.
Yes, Oppo A5s does have a 3.5mm headphone jack.
No. Oppo A5s is not a water-resistant mobile phone.