does i tunes bkup my music on i cloud if so how can i down load to my pc to have my music there and can it sinc like my i phone

Greetings kyote88,

Thanks for using the Apple Support Communities!

From your question, it sounds like your main desire is to download your previous purchases to your Windows computer. This music is associated with your Apple ID and located in the Purchased section of iTunes on your computer and iOS devices as long as you are signed in to the same Apple ID.

To download past purchases, please review the instructions in the following article.

Download your past purchases - Apple Support

The second question about syncing when you purchase more sounds to me like you would like all of your devices to include the new purchases as soon as the purchase is made from any device.

If that is correct, there is a solution and it is called Automatic Downloads. For information on setting up and using Automatic Downloads, read over the information in the next article.

Turn on Automatic Downloads - Apple Support

Have a great day!

Purchases from the iTunes Store may be available to redownload at a later date, but iTunes doesn't backup other media as a rule. A subscription to iTunes Match can backup some of your media but for a robust method see Backup your iTunes for Windows library with SyncToy and Make a split library portable. A portable library can be easily backed up, restore, or connected to any computer running the same build of iTunes.

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