I would now like to set up my Windows 10 laptop, I have a Qwerty keyboard and I do not know which language I should choose because I have a lot of English as a choice
Qwerty is English. Whether you choose US or UK English is up to you as you would like to have the character assignment.
And how do I find what I have on the keyboard?
As a rule, English (United States) should fit.
If you choose English and have an English keyboard, then all keys are identical to the printed characters - what would you like to find there?
If you mean German special characters, then it is advisable to use a keyboard with a German layout and to select German as the language.