First layer for an uneven wall

[AdamOfLondon]

I have bought a house that requires renovation and I have spent a considerable amount of time reading material and looking at videos for smoothing and painting uneven walls.
The walls are drywalls build on 1991, and they are already painted, but they require fixing holes and smoothing.
Given I want a quality finish and I don't mind buying quality material and spending time on this.

Would "mud" be my first layer? Do I use mud to fill dents and smooth the wall or do I use separate products? Is mudding the same as plastering (and is the Americans call it mudding while the British call it plastering)? What category of products should I use for my first layer, looking for mud online doesn't return much useful information, what term should I use? Do I need to cover all areas of the wall even if they are not dented?

 

[Mottie]

If you want a quality finish, my suggestion to you would be....

 

[AdamOfLondon]

If you want a quality finish, my suggestion to you would be....

Thank you for the suggestion. But the same question still holds (about mudding).

 

[CJRatch]

If you want to try your hand at skimming the wall you'll need thistle multi finish.

I will warn you though it's not as easy as the pros make it look.