How to logout of someone else app store login information?
My apps can't be updated because it's logged into someone else account and I don't know their password to proceed with downloading or updating on the app store.
Apple Change Apple ID: Change your Apple ID - Apple Support
Just remember that if the apps were purchased on someone else's ID and you can't enter the Password for that ID, or they haven't given you access to those apps via Family Sharing, you won't be able to update them. You can purchase them under your own ID if you want.