Can nordstrom gift cards be added to Apple Wallet?

Depends on the Specific type of gift card.

If its a re-fillable debit card, you should be able to add it like a regular card directly in the Wallet app.

If it's a non-refillable gift card to loyalty type card, you would need to add it from the Nordstrom's website or app if they offer that option.

click here ➜ Add, use, and share boarding passes, tickets, and other passes in Apple Wallet - Apple Support