FRANKFURT 25 UNTIL 28OF NOVEMBER! (Frankfurt)

HI GUYS I NEED SOME GOOD TIPS about FRANKFURT ,it will be my first time there but i will not get lost i want to know wich are the best places to go to have dinner with my friends and drink,i would like something modern and not touristic but i would even prefer to visit Museums & some old coffe shop where to go in the morning & what about Christmas market ? I really thank u for ur help !
Romy