Html theme (Oyster) and level of experience and software needed

Could You just tell me if I have to be experienced in html webdesign to use this html theme? What software is needed to easy customization? Dreamweaver? Other?
Or it’s better for non-expert to choose wordpress theme version?
best regards
Marat Dakunin

You don’t need to be an expert but there is a degree of expected knowledge, and it will always be easier to use a WP theme.

FYI if you do go with html - Dreamwever is fairly outdated and it’s very unlikely that the “visual” editor that has will be able to work properly/if at all with modern templates. There’s software like Brackets which is free to download and far better to work with (although is all code not visual editing).