Crthuky

I'm trying to add a hyperlink from some word to point to a section, in LyX. Consider a section called "ABC" and another section "XYZ" which contains the word "abc" - so I would like to make a link from "abc" to "ABC", meaning if reader will click on "abc" it will take him to the "ABC" section.
Previous threads suggested to click Insert->label and then Insert->Cross-Reference but it does do as wanted (it just prints the section number instead without actual link).

How to solve this issue?

You seem to be mixing some general Terminology

In Lyx or word etc whilst editing there are ways to jump backwards and forwards from one cross reference to another those locations may be called bookmarks or labels etc which can be confused with other uses of those terms.

The key is these are internal links for convenience whilst editing.

A second form of link is the HYPER-link which will launch you into space outside the document (or equally could link you back in as if arriving from outside) a typical hyperlink in Lyx is shown as

Hyperlink: https://www.lyx.org/trac/wiki/BugTrackerHome

And both applications use a hybrid form where you can jump to a document followed by an internal address.

This is where most confusion arises since the syntax for an external link may be different than for an internal link.

TeX has a number of packages that assist in adding these features and one package is hyperref that can handle both external and internal references.

You wish to cross reference from internal abc to internal label ABC that's only possible if the two use exactly the same label

So we label the section ABC and it is that cross reference we need to put in section XYZ to allow us to jump both ways forward or back.

This works for cross referencing in the editor but you will see nothing in the PDF the compiler has not been instructed to load Hyperref so going to Document > Settings > PDF Properties check the Use Hyperref Support and then define your preferred options.

Now when we compile we get red links by default