The BUSD token has to be added at the Testnet Pancake Swap page manually and not with the BUSD symbol in the dropdown menu. You have to insert the contract address from below. The BNB can be chosen from the dropdown menu.
You have multiple options: single staking (first) and regular staking (second and third)
In the left column you can see the token which is a part of all staking pools which are listed in the middle column.
In the right column the APY and the total value locked for all pools combined are displayed.
If you click on a pool group, you can see all pools within the group:
The second pool group unfolded
There you can see all pools, like for example BNB:tenBNB. Here your deposits, your balance and the APY is displayed.
If you click on this pool, you can see various buttons to interact with the staking pool:
Ways to interact with the BNB:tenBNB pool
The red buttons are all connected to the input field on their left side. The "MAX"-Buttons insert the maximum value possible into the input field.
On the left side two new pool specific values are displayed: "Total Staked" and "Earned Rewards". The first one shows the total token amount that has been deposited, the latter shows the earned rewards through the staking.
All Buttons explained:
Your Liquidity Pool token get deposited into the staking pool
MAX: "Your balance"
Counterpart to "Withdraw"
The deposited tokens will be withdrawn back to your wallet
MAX: "Total Staked"
Counterpart to "Deposit"
The earned rewards will be claimed to your wallet
MAX: "Earned Rewards"
All of the staked tokens and rewards are claimed to your wallet