Working on building a small exchange, someting like sideshift.ai.

 When a user sends crypto to the deposit adress, he will get a notification that they are accepted by the blockchain network.
 Something like:
" thanks for your deposit, We will now exchange your BTC and send 0.124 ETH  to your wallet. You can now close your browser if you want".

I will have like 50 different coins in total, so not only BTC and ETH.


will this work?
https://cryptoapis.io/products/blockchain-events

Would be great with a free one but i could pay few dollars i have to.
Or maybee some other way of doing it?

Im making an exchange like sideshift.ai.
I have 2 questions.


1. How do i generate a new deposit adress for each new user and each coin?

Like if you want to exchange BTC to ETH, you will get a BTC adress/QR code to send to.
But that unique adress needs to go to my binance account, or at least the deposit has to go to binance account. 
Is there like any API or so that generates sub adresses and then binding them all to my static btc adress on binance?

2. When a user send crypto to the deposit adress, he will get a notification that they are accepted by the blockchain network.
 Something like:
" thanks for your deposit, We will now exchange your BTC and send 0.124 ETH  to your wallet. You can now close your browser if you want".


I will have like 50 different coins in total, so not only BTC and ETH.