My grandma gave me her old iPad and it won't let us use it. It says we need to sign in to it using her info first but when we use her info it says it's wrong even though it's not.

What you're seeing is probably iCloud Activation Lock. Have a look at this Apple Support article, which should help get your new-to-you iPad working for you. Enjoy!

https://support.apple.com/en-us/HT201441

(Here's a tip, in the off-chance your grandmother's password contains some of these characters: make sure any Os and 0s; uppercase Is, lowercase Ls, and numeral 1s are all correct when you enter the password. They can look really similar, especially if you're reading the password off a handwritten note!)

The iPad is connected to a working Internet connection via Wi-Fi, right? I don't think you can get past the first couple setup screens without connecting to a Wi-Fi network, but if you don't have a working connection, you won't be able to deactivate iCloud Activation Lock.

Things aren't adding up. If you went to Settings > General > Erase All Content and Settings, the iPad should have asked for your grandma's Apple ID password, and once it was provided, proceeded to erase everything on the device and turn off Activation Lock and everything. It should then restart and be like a brand-new iPad, not requiring anybody else to sign in—at that point, you should be able to sign in with your own Apple ID. Basically, having erased everything lines up with it missing from the iCloud account, but doesn't make sense of the iPad still requiring someone else's Apple ID to sign in. (By the way, how do you know the iPad is asking for your grandma's Apple ID, and not asking you to sign in yourself as part of the new iPad setup process?)

Earlier you said that you had looked at your grandma's iCloud account to see if the iPad was there. I just want to make sure you were looking in the right place (please bear with me). Here's what I see when I log into iCloud and launch Find My iPhone (see image). Note that if you click the text in the top centre, it shows you a list of all devices attached to the account. Along these lines, I'd also be curious to know what you find under the "Devices" heading on appleid.apple.com. The two should match, but it's just another place to check since it seems that things are funky as it is.

If you don't run across anything interesting on iCloud.com or appleid.apple.com, I could be out of ideas (still report what you find though, something might come to me!). That said, it might be time to book a Genius Bar appointment at your local Apple Store, if you have one (which is generally free until something needs to be physically fixed or replaced). On that note, how new is your grandmother's iPad? You could maybe call Apple Support on its 90 days of free phone support since this issue is related. Contact Apple Support

Wish I could be more helpful. Anyways …

Yes the iPad is connected to my Wi-Fi at home, I have taken a couple pictures so you can see that on signing into my grandma's iCloud and Apple ID account that it shows only her new iPad under the devices and not the old iPad she has given me. I've also taken a picture of the activation lock screen to show you why I know it's my grandma's Apple ID it's asking for, and when I put it in its saying that the Apple ID/password is incorrect even though we know that's not true because I can use it and sign into her account on other devices. I know it's not adding up that's why I'm so confused that it's not working. I am so grateful for all your time in trying to help me but you're probably right I probably need to go to an Apple store and get someone to help me there. Thanks anyway.

This sounds super lame but … have you tried restarting the iPad?

To restart your device, press and hold the Sleep/Wake button, then slide the slider. Once the device has powered off, hold the Sleep/Wake button again for a moment until you see the Apple logo.

Source: https://support.apple.com/en-ca/HT201559

Yes, I officially don't know what's going on here. Those pictures confirmed what I thought you might be seeing, with the exception that the iPad should not be displaying that Apple ID anymore, since it was erased and signed out of!

I did some sleuthing on the Internet, and the word on StackExchange is that "… you will likely need to make an appointment at an Apple Store and provide the Genius on-hand proof of purchase (to show you're the authorized owner) along with proof of identity and they will reset Activation Lock, giving you access to the device." (Emphasis added to help avoid potential surprises at the store!)

Source: ios - How can I bypass Activation Lock? - Ask Different

Best wishes! 😀

Thank you so much iEvan. I'm not sure how I can show them I own the iPad when my grandma gave it to me, maybe I'll bring her with me to the apple store. The iPad it was showing under devices is her new one she just bought for herself. Not the one she gave me incase that was a confusion. Anyway I will def go to the apple store. If you have any suggestions other than bringing my 84year old grandmother with me to the apple store let me know lol. Thanks again for all of your help :)

Just curious what state the iPad is in. Was it reset to factory settings and is now partway through the setup process? If not, what app or service is requesting the username and password?