Verbal | the correct use of [main subject][second noun][-ing modifier]

Thank you very much
i have been analysing OG questoins and concluded the following :

,( please correct me if i am wrong ):

1.if we intend to modify the second noun > best thing is to use which
and which always modify the previous noun .

2. or use -ing after the noun (without a comma)
3. if we want to tell what the second noun did , best option is to make the second noun a subject to a relative clause and insert a verb : (link them with that or another relative word)
[second noun]
...

---