The Connected Accounts page is where you can see all the different services you have connected with Zapier. You can access it from the menu at the top of the screen.
From this screen you can add a new account, view your currently connected accounts, view how many zaps each account uses, and rename, test, reconnect, or disconnect those accounts.
You can connect your accounts to Zapier in one of two ways:
The first option is to head to the Connected Accounts page as mentioned above, click on the "Connect a new account" drop-down, search for and choose the app you'd like to connect, and follow the on-screen instructions.
The second option is to create a brand new Zap in your dashboard, choose the app you'd like to connect in either Step 2 or Step 3, and follow the on-screen instructions.