Account holds what belongs to you rather than to the business: your details, your sign-in, and the subscription.
Business details live in My Business. The split matters in a workspace with several people — changing your own phone number and changing the company's are different actions with different consequences.
Profile
Your name, phone and email.
Your email is your sign-in and where password resets go, so change it deliberately. If you are moving to a new address, make sure you can receive mail at it before switching.
Security
Change your password, and set up two-factor sign-in.
A password change is done by requesting a reset email rather than typing the old one, which is why it works even when you have forgotten the current password.
Subscription
What you are on, when it renews or ends, and where to manage billing — update a payment method, see past invoices, or cancel.
The dates are worth reading rather than assuming. Renews is when you will be charged again. Access ends is when a cancelled subscription stops working, which is usually later than the day you cancelled — you keep what you paid for.
If you have more than one workspace
Your account is one login that can reach several workspaces. Your profile follows you across all of them; what you can do inside each is set per workspace by your role.