You can move this topic to beginners and help.
So sorry for your loss. So far you saw the unauthorized transactions from your coinbase pro account, you should be more careful, it could be a malicious attack or it can be from someone you know. I will advice you to look for malware on your computer for removal or format your computer in a way all malware will be formatted along.
Next time, try use 2fa, it could have helped you. Or, is your coinbase exchange account 2fa enabled? Having the 2fa on another device other than your exchange account will help.
Also, passward your device, do not let anyone has access to it other than you. If it support biometry like fingerprint, you can also use it.
They only show history of orders filled. I wish there was a way to prove that the orders were NOT placed by me.
Why the prove when the fund is gone already. There is nothing you can do than to forget about it.