The 2023 capital loss should appear on line 7 of your 2023 Form 1040. If it's not there, you have to file an amended return for 2023 to apply the loss.
The maximum amount of capital loss that can be applied against ordinary income such as wages is $3,000. If the loss was more than that, line 7 of your 2023 Form should be -$3,000. The remainder of the 2023 capital loss is carried over to 2024, and to subsequent years if necessary, until it is used up. But the remaining loss will not carry over correctly to 2024 if it's not shown correctly on your 2023 tax return. You need a correct 2023 tax return in order to calculate the capital loss carryover to 2024.
