Where can I see how much of an order was paid with wallet balance or reward points?

Open the order from Orders → Manage Orders and look at the Summary card:

• Coupon (CODE): the discount from a coupon, if one was used
• Reward Points (500 pts): the points used and the amount they took off, shown before Total
• Total: the order total
• Paid via Wallet: the part of the total paid from the customer's wallet, shown under Total
• Paid and Balance due: what has been paid so far and what is still owed

The coupon, points, wallet and Balance due lines only appear when they apply, so an order without points shows no Reward Points line.

The customer sees the same split in My Orders on your store, with Wallet and Reward points lines in their order summary.