Julia, a lot of people refer to chord sheets as "tab" but actually tab is when you see those four lines of numbers and dashes that indicate picking, usually for the licks/intro, etc. for songs. Chord sheets give the the lyrics w/ chord names written over where the chord changes occur. They don't include strumming patterns usually. Folks will always tell you to just listen to the song and work out the strum for yourself, and while this is true, and it's good to try to hear the pattern and fiddle to see what works, it can be hard for a beginner to do this. If you check out a tutorial for a particular song that you have found a chord sheet for, they will sometimes give you a suggested strum. If they don't mention it in the video, you will sometimes see it asked and answered in the comments below the vid. Or sometimes I will just search on "strum pattern for such and such song" and will get my answer. If all else fails, D D U U D , "swiss army" strum