Need to change numerical identification of page numbers in Footer…i.e from Numerals 1, 2, 3 sequence onwards to i,ii,iii,iv, v, vi, vii… sequence onwards.
BUT Header Footer Menu does not ‘appear’ as available when selected in the… Using Libre Office 7.5 (New download)
So this looks like “I believe that the solution of my real problem should be in that menu”? Note that this premise is false, and the format of the page number is set in page style.
Also note that “…” is unclear. Selected what and where?
Since no comment/answer is already given, modify your question to make it more informative. Mention OS name and full LO version (with at least four numbers as reported by Help>About LO). Even better, copy this information (there is a button for that) and paste it into your question. Mention also save format (.odt vs .doc(x)) as most advanced features are guaranteed stable only in native format.
Have you already enable the footer in the current page style?
Are the page numbers manual? Or are they generated with dedicated page number fields (with Insert>Field>Page Number)?
What do you mean by “Header Footer Menu does not ‘appear’ as available when selected in the…”? What is the “…”? Do you right-click somewhere?
Remember we can’t see your screen nor your hands on keyboard and mouse, so give as much information as possible to make us understand what’s going and reproduce the issue.