changing my wheels size
 

i have 195/65 R15 tires instead of that i need to fit 205/65 R15 .. did this will make any problems such speedometer or any??

thanks in advance

this will answer your question https://tiresize.com/speedometer-calibration/

CQ, Cabrio and B4 sedans in the USA used 205/60-15 sized tires or 205/55-16 sized tires...

If you run a 205/65-15 all the way around, your speedo will be off, but honestly I've found all of my Audis, including my two Q7s, to have optimistic speedometers. So, a larger OD tire actually helps correct that.

Yeah my B4s speedo has never been precisely accurate.