There are loads of instructions on the internet on how to deactivate your Twitter account, but scant information on how to delete your twitter account. So maybe start with deactivating your account and take it from there:
- Sign into your account on the Twitter website
- Click on Settings and Privacy from the drop-down menu under your profile icon
- In the Account section of the menu, click Deactivate your account
- Click Deactivate
- Enter your password when prompted and click Deactivate account
Reference:
https://www.trustedreviews.com/how-to/delete-twitter-account-2951623