Re: tennis racquets recommendation
You are a beginner. Do not play with Federer's racquet or any control oriented racquet. You will have to have almost perfect strokes to play with that kind of racquet and it takes a long time (years) to get there. For now you are going to think about sweet spot and power. You will get those in an oversize O/S racquet.
Find a store that does demos, and take out several O/S racquets, and play for a couple of hours with them. Then write down what you liked.
Do not focus on the brand. Do not focus on using a racquet that any pro has. Think about head size and sweet spot, how the weight feels to you, and the racquet "feel" as you hit the ball. Make sure it feels just as good on serves and volleys as well as groundstrokes.
Take them back and get some more, similar to the ones you liked. Play with these and write down what you liked.
Then after doing this about 3-4 times, you will start to know what you like. Take out all the ones you liked again, and make your decision.
This could take about a month to do. There is no hurry. Just keep demoing until you are SURE you have what you like.