Option A:
1- Go to Sales Forecast
2- Search by name for the Lead
3- Click Edit/View
4- Check/Edit the Expected Closing Date
Option B:
1- Go to Lists & Contacts then choose Desired List
2- Search by name or number and find the desired lead
3- Click on Open Lead
4- Select Sales Forecast and check Expected Closing Date
To Edit:
5- Click More Actions and edit the required date