There are two forms of Online shopping at Walmart:
If you are making a Walmart Pickup & Delivery order, you will need to link your Ibotta account with Walmart. Once linked, be sure to select all the offers you plan to purchase from the Walmart Online section of the app. This can also be done from Ibotta.com. You can then place your order from your phone or computer. Walmart will automatically send the information to Ibotta and you will get credit for those items you selected in the app that match items in your purchase.
If you are placing an order with Walmart.com, you will receive a percentage based on which category the item is in. Be aware that some categories may not give you any credit. Be sure to read the details. To place a Walmart.com order, you can go to Walmart Online in the Ibotta app and click the Shop button.
Hopefully, this gives you a high-level idea of how to shop online at Walmart.
You can find more details at https://help.ibotta.com/hc/en-us