It is good to view Cryptocurrency addresses like a bank account number in the 'Crypto World'.
Every Cryptocurrency transaction is facilitated through movement between 2 separate addresses.
You will need the address which the recipient wishes to receive at.
You will have to key in this address from the platform you wish to send your Cryptocurrency out from.
You will have to provide the sender with the address which you wish to receive your Cryptocurrencies at.
The sender will have to key in this address from the platform which he/she is sending his/her Cryptocurrency from to transfer you the agreed amount.
If you wish to have a deeper understanding on addresses, you can refer here.