You do need to clarify exactly what you have and what you want to do as your initial post is a little obscure?

Some general comments, adding zeros do nothing to any format be it dDD° MM.mmm' or dDD° MM' SS.sss" or dDD.ddddd° and by writing Lat/Long with some proper delineators then it does make a whole lot easier to understand.

"82.00.000 26.00.000 format" this doesn't mean a great lot and there can never be more than one(1) decimal point in any position format. One can sort of see what you are intending (I think) with the last 3 digits but it's this should not be a guessing game.

....Is adding a 8th number to the numbers necessary like" 026.00000 082.00000

No, not really but if the system wants/expects a zero then do it.

Regards loosing accuracy relative to data format, well No, but this is dependent on the decimal places beit Degrees & decimal degrees, Degrees Minutes and decimal minutes or Degrees Minutes Seconds and decimal seconds. For typical marine systems and relative to the accuracy capability of the Standard Position Service then there is not much point going beyond 5 or 6 decimals degrees, 3 decimal minutes or 1 or 2 decimal seconds and typically the decimal places will be controlled by the system?