Hi @catherinpato_8 ,
Thank you for your post.
Seems like it might be a watchlist. To delete the items on desktop/laptop once your in the list there is a tick box up the top that will select all items and then a delete option next to that.
On the app go to my eBay> watchlist> pencil icon on the right side> select all and then delete option.
Thank you,
Kat