After installation of OpenVPN server following instructions from https://community.openvpn.net/openvpn/wiki/OpenvpnSoftwareRepos

Without generating a new PKI, current certificates can be used for openvpn connections

In order for OpenVPN server to access port 12443 (prohibited by SELinux) command below must be run

semanage port -a -t openvpn_port_t -p tcp 12443

openvpn-server.service file must be moved to /etc/systemd/systemd
directory /etc/openvpn/server must be opened and certificates must be copied here