Before you go to Amsterdam, make a simple plan, work out how much you can actually do in the time in the city.
If each day you only take the tram twice, once to go into the center of town and once back to your hotel, you are likely better off with 'one time use' tickets.
But if you want to flit all over, the pass of the GVB which includes a return rail ticket to the airport. Be aware that with this pass you can only use GVB buses, trams and Metros, not the other buses that are also running in the area.
A good option for you might be the pass that allows you free travel within the city center as well as free entry to some museums and attractions as well as reductions on other things to do in the city.
For more transport information see this question, (remember prices may have gone up.)
Alternatively, if you like cycling and the weather is promising to be good, hiring a bike can be a good option.
Amsterdam is good for cycling, the worst thing for most tourists is that it is too busy. But wait till the traffic lights down the road have changed and get on between the rushes of crowds or wait till after the rush hour, say after 9:00 AM. Get a good map for cyling and work out routes that use cycle routes, you will find that you have many options that way.
I would go to one main museum per day, maybe a small one extra if you see on you really like. Set some time aside for shopping, for sitting outside people watching and enjoy a drink, the traditional Dutch cafes are great for that. You will find them at almost every second corner in much of the city.
These sell drinks from coffee and soft drinks to hard spirits.
Plenty restaurants all over the city, the cheaper ones are mostly in the smaller streets behind the most famous streets or in the general area of sights.
More information about the city on many websites, likely also on in your language. I like this one, as it seems to cover everything.
This is one of the small museums you might like to add, the Houseboat museum.
Photo by Willeke and can be used under Creative Commons rules.