Q: I have two apple ID. Can I merge those account so that I can use the updated Apple ID that I have?

No. Apple ID's can not be merged.

Frequently asked questions about Apple ID - Apple Support

Can I merge multiple Apple IDs into one?

Apple IDs can't be merged. We recommend that you use the same Apple ID in the iTunes Store and iCloud. Using multiple Apple IDs might be confusing and might cause issues with accessing purchased content or using some services.

If you need more than one Apple ID, you can still access your purchased items (such as music, movies, or software) using your other Apple IDs. Learn how to use multiple Apple IDs with iTunes and iCloud.