I have just upgraded my MacOs operating system on one of my older machines from El Capitan to Big Sur. I subsequently tried to open xcode but I get the error:
In order to use “Xcode”, you need to update to the latest version. The version of Xcode installed on this Mac is not compatible with macOS Big Sur. You have “Xcode” 7.3.1. Download version 14.1 for free from the App Store.
When I go to the App Store, the only available xcode that I can see is 14.1 which is for Ventura and therefore not compatible with my current set up and so of no use. How to upgrade to say xcode 13, compatible with Big Sur? I hope it is possible without having to manually download xip file from developers section of apple.
The App Store will only let you download and install the latest version of Xcode.
You answered the question in the last sentence. Download Xcode from Apple's developer site. The site Xcode Releases has Apple's download links for every version of Xcode. Xcode 13.2.1 is the latest version that runs on macOS 11.