Sorry. I edited my post after you quoted me, so I edited back.
Your keyboard resembles a
Monterey K104.
There is only one mention of ARC in the Wiki: and that is of using rebranded Chicony models. The Chicony with large Enter keys seem to have used the same types and layout of stabilisers as Monterey.
Both brands use to have the switch under the horizontal portion of the key (as if there was an ANSI Enter key there).
I would wrap the keycap puller around that portion of the keycap and gently pull straight up just so that it gets loose from the switch.
Then the stabilisers are probably Costar-style stabilisers. : one horizontal around the key switch and one vertical in the upper/right corner.
To loosen the stabiliser, either pull it lengthwise to unhook it from the clip in the keycap on one side and then the other. Alternatively, use a thin screwdriver to unclip it sideways from where it is snapped into its clip in the plate.
There are also Cherry MX keyboards with Costar-style stabilisers, so there are thankfully plenty of videos on Youtube about those.