Select the column you want to lock
Right-click the selected column and choose Format Cells
Go to the Protection tab
Check Locked
Click OK
Go to the Review tab
Click Protect Sheet
Enter a password if needed
Choose the permissions you want to allow
Click OK
To lock only specific columns, unlock all other cells first
Select the cells you want editable
Open Format Cells
Go to the Protection tab
Uncheck Locked
Click OK
Protect the sheet again