Laptop too old for WLAN?

The problem is as follows:

today we got a new internet connection. We used to have a range of 3,000, now we have a range of 100,000. Now the problem:

With my other devices the Wi-Fi works without problems, only with my laptop it is quite weak. My laptop is also around 9 years old.

Could it be that he is just too old for this strong connection?

No, it may be that the router sends the 5 GHz WLAN more, but your notebook needs the older 2.4 GHz WLAN.

Deactivate the 5 GHz WLAN on the router.

Probably only the built-in WLAN is not designed for higher data rates - buy a modern USB WLAN stick for 10-15 euro, this will solve the problem

And how do I do that on the router? I have the Fritzbox 7590

Yes, the laptop may not yet support the necessary standards for such high speeds.
They only came out a few years before 2010 and it is therefore quite possible that the laptop does not yet support them.
A remedy can be a USB WLAN stick, as already mentioned.

If you have a fritzbox you can see at what speed the device was synchronized.

If you use mesh, the fritzbox ensures that the device lands in the correct band (2.4 or 5 GHz).