Hi,
Refer the links and demo projects.
AN 730: Nios II Processor Booting Methods in MAX 10 FPGA Devices
https://fpgacloud.intel.com/devstore/platform/16.0.0/Standard/dualboot-design-example/
https://fpgawiki.intel.com/uploads/0/00/Using_Dual_Boot_MAX_10_Evaluation_Kit.pdf
https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/an/an741.pdf
Let me know if this has helped resolve the issue you are facing or if you need any further assistance.
Best Regards,
Anand Raj Shankar
(This message was posted on behalf of Intel Corporation)