See this TurboTax support FAQ for updating your TurboTax account - https://ttlc.intuit.com/turbotax-support/en-us/help-article/account-status/update-turbotax-account-information/L0YoC0H31_US_en_US?uid=m6zhcm93
As long as you can sign in, you can change your Email address.
Follow these steps to change your Intuit Account credentials directly in the Intuit Account Manager:
Important: Your Intuit Account is connected to all of your Intuit products. Any changes you make apply to all of your Intuit products, including QuickBooks, TurboTax, Credit Karma, and our professional tax products.