They're chords. Barre chords to be exact but that doesn't really matter to you at this point I guess. Hopefully from this you've gained that since all the notes are stacked(?) I guess you could say on the tab, you play them at once. As for how many times you play each chord, and the strumming, you have to get that by ear. If your new to this I would suggest downloading a program called Powertab Editor. Just google that. Then once you have that look for only the type of tab "Power Tab" when you search on ultimate-guitar.com. Once you've downloaded whatever tab it is you want open it up in Powertab Editor. It will give you a really easy to read tab, and you can listen to the program play it. The only bad thing is the notes don't sound realistic. Hope that helps.
Also if you're a beginner, which it looks like you are, you should go with some easier songs first. Switching barre chords quickly is hard.