How do i reset my passcode without erasing my whole phone?

Is not possible.

See -> How to remove your iPhone, iPad, or iPod touch passcode without a computer

How to remove your iPhone, iPad, or iPod touch passcode without a computer - Apple Support

The screen lock passcode, if forgotten, cannot be reset without erasing the device. This is a deliberate design feature of iOS and iPadOS to ensure no one may gain access to a device with intact data without knowing the passcode.

You can restore your data afterwards from your iCloud or iTunes or finder backup. Content sync’d to iCloud (e.g. contacts) will resync when you sign the device back into iCloud.