Question: how to transfer data from samsung s7 to google pixel 3a?
Answer: Insert your SIM. Remove the SIM card from your Samsung and with the tool provided, open the SIM tray on your Pixel 3A. ... 
Connect to Wi-Fi and sign in with your Google Account. Once you have the SIM in place and you've turned on your Pixel 3A, join a Wi-Fi network. ... 
Get your stuff and go.