Yes, you can use one WhatsApp account on two devices. Read following instructions
The first step is to ensure that both phones have WhatsApp installed. Once that’s done, you’ll need to verify your account on the first phone using your phone number. Once your account is verified, you can then move on to the second phone.
On the second phone, you’ll need to open WhatsApp and enter your phone number. Instead of verifying the account using a text message or phone call, you’ll need to select the “Verify through SMS” option. This will send a verification code to the first phone, which you can then enter on the second phone to verify the account.
Once the account is verified on the second phone, you can start using WhatsApp on both devices. Keep in mind that you’ll need to have an internet connection on both phones in order to send and receive messages. However, WhatsApp does allow you to download messages for offline use, so you can still view them even if you don’t have a connection.
Additionally, WhatsApp’s end-to-end encryption only works on one device at a time, so if you’re using the same account on two phones, you’ll need to choose which one to use for encrypted conversations.