How to fix Iphone 12 pro which stuck on the Apple Logo?

My phone memory is full and its stuck on the Apple logo. Last night the backup did not work.

Tried to do update today but the device keeps disconnecting from the Finder. It is on a loop.

Any help, please, I don't want to use the 'Restore factory settings' in Finder because have treasured videos and audios with my Mum.