To manage your portfolios, go to the "Holdings" tab in the Generator
Select the portfolio you want to manage from the portfolio list at the top.
Scroll the list to find the stocks you want to edit.
To edit a stock, select the icon at the top right corner of its card - see the yellow highlight in the screenshot below.
To remove the stock, you can delete it by selecting Delete Holding. To modify the stock, you can select Edit Holding in the interface that follows - remember to press the Update Holding button to finish.