Can i access remote SQL server via VPN without firewall?

I’m totally new in SQL Server.But I’m going to work hard on it in this periode. There are two remote SQL server: Server A and Server B. I want to access data of Server B from Server A. Server B does not have firewall and its is a simple router/modem for particular. Can i access Server B via VPN without firewall?
Normally, in order to connect remote SQL server,default port 1433 and TCP/UDP should be enable. But without firewall, is the connection still possible/available? Any tutorial about this topic will be thankful!
If my question does not formulated correctly, please let me know.
I appreciate your time and help.