How do I transfer 1 amount of BNB to the BSC address? And automatically receive back 1 of the pre-booked tokens

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How do I transfer a BNB amount to the BSC address in Metamask?
And automatically get back 1 of the tokens I have reserved.
For example I have token: xxx
When I transfer some bill to the BSC address in Metamask
Thi automatically I will receive back 1 amount of token: xxx
please help me