Find Duplicates and add columns while shifting the cells up

I have a list of 3 columns with the following headings

ID Quantity Info

there is a long list of items
I want the code to find any duplicate items based off the ID column.
I then want the quantities to be added for the duplicate items from the quantity column.
I want to then get rid of the duplicate lines so there is only one line for that item. the info column will be the same for the same item.

a Pivot table will not work for this because i have many other codes acting on this data this is just one step in the process.

any help with this would be awesome

To simplify the code it doesnt have to delete the duplicate rows after adding the quantities. I'm sorting them after this so just deleting the contents of the cells will be enough. after i sort it, it will go to the bottom.

thanks
JD

JD,
Please attach a sample.

Attached is an example file with a small amount of data with the desired results also

Output in new sheet