I accidentally put tuition fees in for this year that were actually from 2023 and then claimed the training rebate. How do I fix this?

You would have to remove your 2023 tuition from your 2024 return. Then you can add it to your 2023 using ReFile and claim the Canada training credit for that year. This TurboTax Canada FAQ tells you how to use ReFile: https://turbotax.community.intuit.ca/turbotax-support/en-ca/help-article/accounting-bookkeeping/filed-tax-return-still-make-changes/L992Trv7f_CA_en_CA

 

 

If you didn't have tuition for 2024, then you can't claim the Canada training credit for 2024.