「が」(ga) vs 「は」(wa) when it comes to specifically "this" object / referring to self

Question

Learning particles and looking at wa vs ga. From what I have seen wa is the topic/general and ga is for the subject/specific.

I was watching this video which had the following example:

I like Van Gogh's paintings.

Gohho no e ga suki desu.

I understand they are talking about Gogh's paintings specifically so they used ga, but since there isn't plurals in Japanese from what I have learned so far and ga was already used to refer to Gogh specifically and not a specific painting, how does one express the following?

I like this Van Gogh painting.

Fumbling around with translators it appears the entire sentence changes to add this and I become the topic whereas before I was omitted.

Watashi wa kono Gohho no e ga suki desu.

Still learning the basic sentence structures, but is that correct? Because I added this/kono, the entire sentence must change to include myself as the topic? I was expecting to just be able to place kono somewhere in the original sentence. When do I know I need to use Watashi instead of just desu?

Answer 1

I believe I figured out my confusion. Because watashi was omitted in the previous sentences I learned, I thought desu filled in the gap because I misunderstood what it meant in TyCobb desu.. The textbook automatically omitted Watashi wa so I thought desu referred to I in certain situations/contexts.

Upon further research, it is to be, is/am or used to end a sentence after a noun or adjective. This made me realize that suki in Japanese is a na-adjective or noun or both? Need to revisit that, but it's not a verb like it is in English.

So if what I have read is correct, this should be correct:

Kono Gohho no e ga suki desu.

And if I understand writing (or at least typing and checking the chart) in hiragana correctly:

このごっほのえがすきです。