internet traffic secure? (new to vpn)

[regnarts]

I'm new to VPN and just started to using OpenVPN today with the setup in my router. I did a little research but couldn't find anything satisfying. I understand that the connection between my iPhone and local network is secure but how about when I go online like to youtube.com. Is that data and connection secure too? Can whoever monitoring traffic tell that I'm on youtube.com? And is it the same for say, on a laptop? Thanks!