Norwegians speak excellent English, especially in tourist areas. Nearly everyone, including in the more remote regions like the Lofoten Islands, speaks English well, so communication should not be an issue. Signs in museums, tourist attractions, and restaurants often have English translations.
Public transportation, such as buses and ferries, are user-friendly, and signage is often in English in addition to Norwegian. The same goes for driving, with road signs being easy to follow.
While the Lofoten Islands are remote and sparsely populated, the tourism infrastructure is well-developed, and locals are accustomed to English-speaking visitors. Even in small fishing villages, you’ll likely encounter English speakers.
There's no real need to learn Norwegian unless you want to enhance your cultural experience, but a few greetings like "Takk" (Thank you) or "Hei" (Hello) might be appreciated.