What should you do?

Answer: See the explanation

Explanation:
Step 1: configure key ring
crypto ikev2 keyring mykeys
peer SiteB.cisco.com
address 209.161.201.1
pre-shared-key local $iteA
pre-shared key remote $iteB
Step 2: Configure IKEv2 profile

Crypto ikev2 profile default
identity local fqdn SiteA.cisco.com
Match identity remote fqdn SiteB.cisco.com
Authentication local pre-share
Authentication remote pre-share
Keyring local mykeys
Step 3: Create the GRE Tunnel and apply profile
crypto ipsec profile default
set ikev2-profile default
Interface tunnel 0
ip address 10.1.1.1 255.255.255.0
Tunnel source eth 0/0
Tunnel destination 209.165.201.1
tunnel protection ipsec profile default
end