My PC won't run After Effects due to the processor generation I wanted to download version 23.x. how i can ?

Hi, CORCTON's method is correct in general, but AE 23.x has been retired and no longer appears in Creative Cloud's "Other versions" list. Only 25.x and 26.x are currently installable.

I'd suggest upgrading your computer. Refer to the system requirements page shared by the ToolfarmJP.

Sorry it isn't better news. Let me know if there are any other questions.

Thanks,
Nishu

You also check the system requirements.

https://helpx.adobe.com/after-effects/desktop/get-started/technical-requirements/system-requirements.html
 

Hi! You can install an older version through the Creative Cloud desktop app: open the app, go to Apps > All apps, click the ⋯ (more actions) button next to After Effects, choose "Other versions", then select 23.x and install.

Just note that only the versions Adobe still makes available will appear in that list.