Hello Duccomputer,
We'd like to help with the issue you've described so you can continue downloading from the iTunes Store.
Based on the information you have provided, it appears you're currently not able to complete downloads from the iTunes Store due to error codes you encounter.
If the above is correct, have you been able to successfully complete iTunes Store downloads in the past? If so, did any recent change occur on your computer? Perhaps a software install or the use of a security software?
Check this resource for general steps to take to resolve error codes on iTunes: If you see an error in Finder or iTunes on your computer
Let us know how it goes.