need help sync an old apple id to a new one

Your Apple ID is the personal account you use with all Apple products and services. It includes the email address and password you use to sign in, as well as the contact, payment, and security details that you use with Apple.

You can’t merge & sync multiple Apple ID accounts.

See the following Apple articles

Sign in with your Apple ID -> Sign in with your Apple ID - Apple Support

Manage and use your Apple ID -> Manage and use your Apple ID – Apple Support (UK)

i know my username and password for my old account it just i needed to create.

If you know your username and password for my old account, don't create a new Apple ID.

cuz wouldn't let me take off my card info eveytime i would go to download an app it would me to update my Card info to even download free apps

You can download free apps, but you may need to have a valid payment method on file, even if the app you want to download is free. 

Free apps has also In-app pruchase.

See -> If you can’t download or update apps on your iPhone or iPad

If you can’t download or update apps on your iPhone or iPad – Apple Support (UK)

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Add a payment method

You may need to have a valid payment method on file, even if the app you want to download is free.

Add a payment method

• If you want to change your card, add first the new card, then remove the old one.
• or if you want to use your Apple ID balance, you need to set your Apple ID balance as your default payment.

See also the following Apple articles:

If you need to change or update your Apple ID payment method

If you need to change or update your Apple ID payment method - Apple Support

Remove a payment method from your Apple ID

Remove a payment method from your Apple ID - Apple SupportP

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If you can't remove a payment method

If you have subscriptions like iCloud+, have an unpaid balance, or you use purchase sharing, you must keep at least one payment method on file.

• Do you have a subscription? You can cancel iCloud+ and cancel other subscriptions from Apple. When your subscription period is over, remove your payment method.
• If you're in a Family Sharing group and you use purchase sharing, the family organizer must have a payment method on file. If you're the family organizer, turn off purchase sharing, then remove the payment method.
• If you have an unpaid balance, you might not be able to remove a payment method. Instead, change your payment method.
• If you still can't remove a payment method, contact Apple Support.

Payment methods you can use with your Apple ID

Payment methods you can use with your Apple ID – Apple Support (UK)

fyi: Not all credit & debit cards seem to work with App Store / iTunes Store, try a different one, or preferably a credit card. If your card is not accepted as a paymenf method, you need to contact your bank.

If you still need help, get support from Apple directly -> Get Support or call Apple in your region see -> Contact Apple for support and service or check -> here for more support and assistance.

Merging, splitting or transferring items between Apple accounts (IDs) is for the most part not officially supported. Read the links below for things you may need to do to transfer as much as is possible and to share some others.

It isn't true automated syncing as would take place if multiple devices were using the same ID and were connected to iCloud. Some services are set up for simple sharing, but using the method described in a later part of this post isn't something you would want to have to do routinely.

Apps and media bought with one ID are permanently associated with that ID. Look into using Family Sharing to continue to be able to use items purchased with one Apple ID with other Apple IDs, and for some data sharing features.

- Family Sharing - What is Family Sharing? - Apple Support

- Set up Family Sharing - Set up Family Sharing - Apple Support

Share folders with iCloud Drive --> Share files and folders in iCloud Drive on iCloud.com - Apple Support

Read How to use Shared Albums in Photos on your iPhone, iPad, and Mac - Apple Support about how to share photos.

If you have signed into the first ID on a device then fortunately when you sign out of that ID, do not erase the device, then sign in with a different ID, it asks you in most cases if you wish to merge the data from the two IDs on your device (toggle the ones you want to on). Say yes and later delete individual items from the other ID that you do not want. Note, in How to save apps and progress on one Appl… - Apple Community a Community Specialist says, "you will not be able to transfer the meta data from one Apple ID to another. Once you switch to another Apple ID the information associated with the old Apple ID will be gone except for physical content on the device like photos and videos." Also turn off storage optimization before doing this. With Optimize Storage, smaller, space-saving photos and videos are kept on your device while all of your original, full-resolution versions are stored in iCloud. Make sure photo optimization is turned off. Manage your photo and video storage - Apple Support

Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac --> Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac - Apple Support

If another Apple ID is signed in you may need to enter the password for that ID to sign out of that ID first.

Click on this link to learn how to 'Sign in with your Apple ID' --> Sign in with your Apple ID - Apple Support