Difference between oxo and formyl
This question was downvoted. Someone said Oxo is only used for ketone in the comment. I did some research to disprove that and shared this link in the comments.
It is a Quora blog written by "Kurt Van den Broeck".
ALDEHYDES:
If they get priority in the name they get the suffix ‘al’ or ‘carbaldehyde’ As substituent prefixes ‘oxo’ and ‘formyl’ are used. The prefix ‘formyl’ is used in preferred IUPAC names, except for a -CHO group at the end of an acyclic chain.
And it also answers my original question. I thought of answering my own question by quoting from the link but he did not provide any source for his claim, so I choose not to answer my own question as it also may get downvotes. Is there any way to improve this question?