IPhone memory too full to transfer data?

I have a problem that has annoyed me for a long time with my iPhone X.

I have overloaded my cell phone with around 20,000 pictures, around 2,000 videos and some apps. 😑

I have had the cell phone since 2017 and have really "cleaned out" everything that I don't really need. What is left of media are extremely important vacation pictures, business matters etc. Which I would like to save on an external hard drive.
Unfortunately, it doesn't work at all, no matter which PC I try, the PC or laptop hangs up, it doesn't show any pictures or or or. It just doesn't work no matter what I tried. I'm desperate 😩

My question now is whether I can take the cell phone somewhere for data backup where it can be done quickly? And if so - where? At Apple directly or in a normal cell phone shop?

I need the phone for work and now I can no longer open some apps (e.g. WhatsApp) 😂

I very much hope that someone can tell me where I can go and how long it takes.

If you attach it to a Windows PC, the Windows version of iTunes must also be installed on the PC. Then it works with the connection and you can simply "slide over" the pictures.

Use iCloud or Google Photos

I use iCloud, but I want to save the media on an external hard drive

Okay, thanks for the quick reply. I'll try that with ITunes. 😊

ICloud is definitely more secure than an external hard drive.
But go to icloud.com, download the pictures and then drag them to the external hard drive.