Installing macOS Sequoia on your iMac with 1TB of storage and 8GB of RAM is not feasible due to hardware compatibility requirements.

Compatibility Requirements

MacOS Sequoia, announced at WWDC 2024, is designed to run exclusively on Macs equipped with Apple's M-class chips. This means that only newer models such as those featuring the M1 or M2 chips will support the full features of this operating system, including the new generative AI functionalities24.

Current iMac Models

If your iMac has an Intel processor (common in models prior to the M1 chip), it will not be compatible with macOS Sequoia. The last version of macOS that supported Intel-based Macs is likely to be macOS 14 Sonoma, which was released in September 20235.

Conclusion

In summary, if your iMac is running on an Intel processor, you will not be able to install macOS Sequoia. You may want to consider upgrading to a newer Mac that supports the M-class chip if you wish to utilize the latest macOS features.