Printed sheet music in standard notation to Tablature for guitar?

I need help please to take printed sheet music in standard notation and getting it into tablature for electric guitar. I am a newbie to MuseScore and am desperate at this point. I am a mom who is clueless about guitar and tech and my son received sheet music for a concert in standard notation. He is mostly self taught and does not know yet how to read standard notation and he has a concert in 2 weeks. His band teacher does not know guitar (only brass) and so he's been on his own. The answer may already be in the forum somewhere but I haven't been able to locate something that doesn't look like an entirely different language to me. I would really appreciate anyone who can clearly outline the steps I'd need to take. Thank you so much in advance for your guidance!