Hello: Dobri den, Thanks: Dicky, pronunced Jicke.
25USD a day.
Sleep: Dorm at a hostel, 250-300 cz. I stayed at Blind eye hostel which was nice and like 3 tram stops from the old town.
Eat: Buy food at the supermarket, the quality is great and prices low. How much you spend depends on your cooking.
Transport: There’s rarely officers checking if you have a ticket or not, so I advice not buying one and speaking in your native tongue if you get caught.
Party: Theres many free parties, payed ojes are good as well and go for around 100-200cz.
What to do
My recommendation, in any big european city, is getting a free walking tour. I strongly recommend the sandemans ones, the spanish ones are awesome and very informative, check their webpage for more info. After you have done the walking tour explore the city on your own, cityspy maps are a great help for this and you can find them online or usually at hostels. Prague is a city with a lot going on durinbg the day and night, during the fay enjoy the many street performers around every spot of the city nd at night go watch an opera, or just party till the sun comes out.
Tram number 17 goes all the way to a big park where theres no tourists, great spot for chilling.