Without the information requested in my previous response, I can only give you a general answer, but I hope this helps.
Please follow the below steps to delete YouTube channel:-
Step 1: Sign in to YouTube with the channel you want to delete.
Step 2: In the top right, click your account > YouTube settings .
Step 3: Under 'Account settings', select Overview.
Step 4: Under the channel's name, select 'Advanced'.
Step 5: At the bottom, select 'Delete channel' (you may see Delete content instead). If prompted, enter your sign-in details.
Step 6: Select I want to permanently delete my content.
Step 7: Select the boxes to confirm you want to delete your channel.
Step 8: Select 'Delete my channel' (you may see delete my content instead).
After the deletion of YouTube channel, the data associated with the channel, such as watch time, will still be part of aggregate reports, but will not be attributed to the deleted channel. Apart from this, the channel URL and channel name will no longer be visible or searchable in YouTube Analytics.