Do we need to have ethereum wallet only if they pay us ethereum token?
Yes. As the name says, the token works inside the Ethereum chain. So they are stored in your Eth address.
And with regards to bitcoin wallet, i have already coins.ph app. Is it okay?
Coins.ph is an exchange and not a wallet. The best option would be to use a desktop wallet where you control your private-keys (such as Electrum).