IPFIX is defined in RFC 7011, Specification of the IP Flow Information Export (IPFIX) Protocol for the Exchange of Flow Information. Much of what you do or do not have in your records is up to the specific implementation. Your application is off-topic, but if you look at Appendix A. IPFIX Encoding Examples, it will give you some example templates, and the meanings of the fields for those templates. For example:
A.2. Template Set Examples
A.2.1. Template Set Using IANA Information Elements
We want to report the following Information Elements:
IPv4 source IP address: sourceIPv4Address [IANA-IPFIX], with a
length of 4 octets
IPv4 destination IP address: destinationIPv4Address [IANA-IPFIX],
with a length of 4 octets
Next-hop IP address (IPv4): ipNextHopIPv4Address [IANA-IPFIX], with
a length of 4 octets
Number of packets of the Flow: packetDeltaCount [IANA-IPFIX], with
a length of 4 octets
Number of octets of the Flow: octetDeltaCount [IANA-IPFIX], with a
length of 4 octets
Therefore, the Template Set will be composed of the following:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 28 octets |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID 256 | Field Count = 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| sourceIPv4Address = 8 | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| destinationIPv4Address = 12 | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| ipNextHopIPv4Address = 15 | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| packetDeltaCount = 2 | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| octetDeltaCount = 1 | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+