These Practice pages can be utilized in several ways.

The recommended method is for two partners to be in vocal contact, each looking at the page in a different computer - perhaps one with a laptop. Using this method one partner would start by clicking on NORTH, the other on SOUTH.

Somewhat less satisfactorily, the partners can use a single computer, and alternate looking at the display, again one as NORTH, the other as SOUTH.

As a last resort, one person can click back and forth between screens.

Start by clicking one of the buttons; when the bidding is complete click the BIDDING button to check the "recommended" bidding.
 You are the Dealer.
 Bid this hand with your partner.
 The opponents do not bid.
 Your partner, NORTH, is the Dealer.
 Bid this hand together.
 The opponents do not bid.

Just having a 4-card Major doesn't mean you must automatically use Stayman.

Here SOUTH has a 4-card ♠ suit, but decides not to seek a 4-4 fit because his hand wouldn't have any ruffing values in a ♠ contract. He bids 3NT.

Notice that even though NORTH also has four ♠s the 4-4 fit is not useful to them in a ♠ contract because neither hand can ruff any losers.
♠ A Q 6 2
K J 8
A 6 2
♣ K 8 7

♠ K J 7 3
Q 9 5
K 10 4
♣ Q 9 3