I see you're only 17, so I'm going to be straight up with you: this is a prime example of why we advise learners to think in a language, instead of translating. I'm not really clear about where the store is (I assume the phrase is part of a longer description), but you might say something like this: la tienda está a unos / varios / cuatro metros (al sur / norte, etc) de la Calle Oak.

Does"right off" mean immediatly? I will traduce like "La tienda está justo en la calle Oak" or "La tienda está sin ninguna duda en la calle Oak"

If the meaning is "immediately after", then you would say "justo después". For example: Si tienes sed hay una fuente en esa dirección, justo después de la iglesia.

Thank you very much for the reply Su.Ki, I should specify and clarify that I don't speak British English; you not knowing it could mean this phrase is a colloquialism that's A LOT more common or exclusive to America than Europe (not fully sure). I'm thinking a better way to express this would be "immediately after" , "just off of" or "off to the side of".

It might help if you explained in clearer terms what you mean by 'right off of'. I'm a native speaker, and I'm not sure myself what 'right off of Oak Street' means'. Nor would the majority of native Spanish or French speakers who have learnt English in France, Belgium, Switzerland or Spain. In Europe, most people learn standard British English, and this expression may be unknown to them.