You use the D-pad to adjust the angle and the "A" button to set power.
No, Angry Birds 2 was not officially released on the NES console. The game was developed for mobile devices, and its release was limited to iOS and Android platforms. As a result, there is no official Angry Birds 2 NES ROM available for download. angry birds 2 nes rom download free
Look for "Angry Bird (Unl)" or "Angry Birds 2 (China) (Unl)". You use the D-pad to adjust the angle