I'm not sure what you mean by that context. May you elaborate?

I'm guessing that you want to buy all the parts for something you built online...the only thing I know of is to create a list and then go to a parts warehouse and buy the individual parts.
bricklink.com
brickowl.com
some place like those...I don't know that there is something that lets you export the part list...hope this helps...

You can get a bricklink inventory list from your own and others models(if they are public), there are two ways to do this.

1. If the model is public you can click on "INVENTORY" under the 3d-player and then choose between CSV och bricklink xml file.
   To acces your own public models you can use this link with your own username at the end instead of "Sealund"
   https://www.mecabricks.com/en/user/Sealund

2. If it's your own model and it's not public you can use the url:

http://www.mecabricks.com/inventory/bricklink/MODEL_ID.zip

where MODEL_ID is the 11 chars alphacode of your model.

For example:
This is the model page with alphacode b82x1XNkj1z: https://www.mecabricks.com/en/models/b82x1XNkj1z
And this is the url to download the zip file : http://www.mecabricks.com/inventory/bricklink/b82x1XNkj1z.zip

To get a csv file from a non public model you do the same but with this url:

http://www.mecabricks.com/inventory/MODEL_ID.csv

For example:
http://www.mecabricks.com/inventory/b82x1XNkj1z.csv