How am I suppossed to take off the sreen time if I don'''t remember the passcode?

Click on the link to read what to do "If you forgot the [restrictions or ScreenTime passcode] for your iPhone, iPad, or iPod touch, or your device is disabled" --> http://support.apple.com/HT204306 - You can restore from a backup but that backup has to date from before you set the restrictions/Screen Time passcode.

Sorry, but there is no way to remove the screen time passcode without erasing the phone an setting it up as a new device, and not using the latest backup afterwards. The backup contains the code as well, so only a backup taken prior to setting up the code could save your other data.

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Make sure to choose a passcode that's different from the passcode you use to unlock your device. If you can't remember a restrictions passcode that you set on a previous version of iOS or iPadOS, or you forgot your Screen Time passcode, you need to erase your device, then set it up as a new device to remove the passcode. Restoring your device from a backup won't remove your passcode.

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copied from: Prevent in-app purchases from the App Store - Apple Support

Make sure to choose a passcode that's different from the passcode you use to unlock your device. If you can't remember a restrictions passcode that you set on a previous version of iOS or iPadOS, or you forgot your Screen Time passcode, you need to erase your device, then set it up as a new device to remove the passcode. Restoring your device from a backup won't remove your passcode.

The above is from this article........Prevent in-app purchases from the App Store - Apple Support

As you can see, everybody else is providing the same link to the article I provided (If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support), so probably that's your solution. ;-)

Read carefully what I said about restoring from backup. Advice telling you that you cannot restore from backup is not completely correct. As I said you can restore from backup but that backup has to have been made before you set the Screen Time code. If you restore from a later backup then you just re-install the forgotten code.