Preheat your air fryer to 400°F to ensure a perfectly crisp texture.
Slice the potato into thin wedges and toss them in a bowl with half of the avocado oil and a pinch of salt and pepper.
Place the potato wedges in the air fryer basket in a single layer and cook for 15-18 minutes, shaking the basket halfway through.
In a shallow bowl, whisk together the whole wheat flour, light beer, garlic powder, paprika, and the remaining salt and pepper until a smooth batter forms.
Pat the cod fillets completely dry with a paper towel, then dip each piece into the batter until fully coated.
Lightly coat the air fryer basket with the remaining avocado oil, place the fish inside, and air fry at 400°F for 10-12 minutes until the coating is golden and the fish flakes easily.
Serve the crispy fish alongside the potato wedges with a fresh lemon wedge for a bright finish.