Answer to "where is the Settings page".
This article describe where to find the Settings Page.You can find Settings, by clicking on your "user name" on the right top corner of your screen.
You will get many options inside Settings Page, through which you can customise you Account.
Site Setup is one of the option provided by the Settings Page.
Here, you can edit your Team Id and API Key.
You also get Site Code which lets you track customer behaviour on your website and market to them more effectively.
Then comes the Account Details. You can go this link for more details.
Under the Preferences, you get option of changing your Default Email Editor from Drag and Drop to Plain text Editor, you also get option of changing Newsletter Archive from Show to Hide.
Then comes the Integrations, here you can add New Integrations or Edit an existing one.
After the you get the Templates option, where you can "make your own" Template or "edit a existing one" and also you can "delete" a template from here.
Under SMTP Providers, you can connect to "Third Party" service provider using SendX.
Under Members and Teams, you can "add" as many team members or "delete" a member as per requirement.
For Billing Details, you can go to the given link to for all the details related to invoice.