do they have mixed drinks
Excellent white wine is available. Never drink mixed drinks myself but see no reason they shouldn't be on offer.
In a restaurant or bar they have anything you want, wine, beer, spirits, soft drinks, coffee.
What are you looking for?
Edit: I've just noticed this is a duplicate post. You asked the same question and got lots of answers some months ago. See here: https://community.ricksteves.com/travel-forum/germany/drinks-in-germany
Why do people do this, Chris? Or rather, Roberta, why have you asked this question again?
Schnapps is a classic, but it won't quench your thirst. As an alternative to straight beer, there's "radler," a refreshing, half-the-alcohol, sweeter and lighter drink that's half beer and half lemon-lime soda. Bicyclists drink it so they can drink some, but not get so tipsy they'd fall over on their bikes.
There's always bottled mineralwasser, too.
Flexibility is required in international travel.
In Germany, you must be flexible: drink 1 beer, at least, please.
In germany at coctail bars, especially in the north (but increasingly all over), the national coctail is, ironically, the brazilian Caipirinha (germans call it a Kaipi).
You may also enjoy the lighter summer beverage Aperol Spritz, which is wine, aperol, citrus, and soda, usually in a wine glass. Great on a humid day. Or its increasingly popular cousin with elderflower syrup.
In the south of Germany, mixed drinks are not as popular as they are in Berlin. Often cocktail bars serve overblown massive ice-cream looking things and call them mixed drinks. Lots of fruit and umbrellas etc. Otherwise people enjoy beer or wine. Fortunately the southwest of Germany has some of the nicest white wines in all of Europe.
To the person who responded that the questioner should be "flexible" and drink at least one beer:
Sure, she was asking about mixed drinks as an alternative, but there are other people who cannot drink. And even if she CAN drink, many people simply DO NOT like beer. Why should she FORCE herself to drink/eat/do something she doesn't want to?
I don't like the taste of any alcohol at all, and when I go to Germany in September I will not be drinking beer because, despite more than a decade of repeatedly trying to get myself to like the taste of alcohol, it doesn't work for me. Instead, I will go enjoy the experience of a beer hall and happily sip a Coke Zero (or water).
Would you tell a Muslim or Jew to be "flexible" and eat at least one pork sausage? I'm all for trying new things when you travel, but everyone has limits as to what is enjoyable to them.
The best pork and veal sausage is the Schweize Bratwurst. No problem in not drinking beer, drink the Mineralwasser or Brause, or Karamalz.