Remote cell phone control?

My cell phone recently broke down completely; the display doesn't work anymore. At first I decided not to transfer any data at all, but now I need a few, just bypassing the contacts. The touchscreen still works, so some simple things are still possible. Is there a remote app that I could use to verify my accounts because I'm emailed a PIN on the broken phone that works from the PC? And which I can best download from the PC (Win10) to the mobile phone (Huawei P20 still has Google!), Via USB, for example, and with a password query, I still know that.

I recently had a similar problem with one of my Huawei devices.
Your P20 has a USB-C 3.1 socket, which allows you to use a USB-C hub with HDMI and USB to transfer your screen to a monitor or TV.

With this you can then see your phone screen. Unfortunately not in the screen where you have to enter your password. You have to do it blind somehow.

With this method, you plug a USB into your hub, for example, and then drag important data to this stick using the file manager.

If your PC already has ADB access, you can use a tool called "scrcpy" to transfer your mobile phone screen to your PC as well.

Here you can - as soon as you have access - select the loading mode "Transfer files" and then access your mobile phone memory on your PC.

How do I get the picture from the USB-C input to the TV? Do I need an adapter there?

Yes, you need such an adapter. See https://www.amazon.de/...075FGQ988/

You plug it into your cell phone and plug in an HDMI cable there and connect it to a monitor or TV.