Every Bonfire night/Christmas/New year there are threads on this.
Most dog owners will know the basics:
Behave normally, have the radio on
Ensure dog has a safe dark comfortable den to hide in
Offer reassurance - you cannot reinforce fear
Long walk during the day to tire out followed by a good feed - more likely to be content and less reactive
Distract with licki mats/frozen kong etc
But also:
Get your dog checked for chronic painful disease - arthritis and dental disease are common and noise phobias are strongly correlated with chronically painful conditions. Treating the pain has been shown to reduce noise phobias (and is good for welfare)
Start firework desensitisation therapy using apps played at low volume or the 'sounds scary' resource.
Use appropriate medication:
Speak to your vet - sileo and pexicon are the licensed medications and can be game changing
Also pain relief if there's an underlying painful condition.
For milder anxieties supplements like zylkene, yucalm etc may help - again speak to your vet or behaviourist.
Adaptil (pheromone) alone is unlikely to make any difference in a phobic dog. Genuine panic/phobia usually needs medication
Thunder shirts and other complementary approaches can be helpful for some dogs but the response varies