How to add / testfor @a {Inventory: [{Slot: 100b, id: minecraft: diamond_boots if it has a specific tag, for example: Ski?

I'm building a project with commands

I'm not sure right now. But should actually go by name: "name". Would in Command then look like this:

/ testfor @a {Inventory: [{Slot: 100b, id: minecraft: diamond_boots, tag: {name: "Ski"}}]}

Quasi added:, tag: {name: "Ski"}

Could be totally wrong. Maybe it is correct and there's still a punctuation error or so in there. Just try it, let me know if it worked. If necessary, be available for further questions.

It does not work

Which version?

/ testfor @p {Inventory: [{Slot: 100b, id: minecraft: diamond_boots, tag: {display: {name: "***"}}]}