VPN tunnel between three devices - two Public IPs and one Private

Hello!

I would like to connect three routers using VPN tunnel.
Two routers have public IP and one has private IP.
I would like also to ping hosts between LANs, for example: host from LAN 10.10.10.0/24 has to be reachable from 10.10.11.0/24

In my opinion there can be a problem with Router R1 which has Private IP.
Can I use host to host connection between R1 and R2, or it has to be client to host connection?

I`m thinking about using L2TP/IPsec protocols.

Please see attached topology.

R1 - Mikrotik RB450

R2 and R3 - Ubiquiti EdgeRouter