Each time I make a new scan, additional channels( that I did not scan) are added to the newly found channels under its respective satellite name. I guess these channels are preset in ProgDVb. How do i get it rid of it? I even try to use ProgEdit but It's very annoying with a long list of channels. Where is it stored in ProgDvB?

You can remove all losted channels in last page of scanner report.
Or in channel list.

What I mean is that some channels came preset with ProgDVB. Even If i scan one transponder on a satellite and get 8 channels, I would then see some 50 channels listed . These channels/providers, I think come with Progdvb. Just want to know where it is stored / how can i get rid of them. Here I do not receive European channels on W3A but even this, they are listed.

Did not play around with recent versions to much, but there's one chance, to scan in channels from transponders, that weren't tuned in, automatic NAT scanning being activated.

There are tables on some satellites' transponders, that carry additional information on stations on other transponders. So, on that satellite systems, like Astra 19.2°E, tuning to one seed channel ( / transponder) would be enough, to hop from one transponder to the other automatically and scan in the whole thing, even including new transponders, that are yet missing in the transponder list used.
AFAIK, ProgDVB has an option to use NAT now.
Perhaps you may want to deactivate this, to compare.

To be sure to not have any default or old station entries in your list(s), you can delete the whole content of the Channels folder. You would then have to define new channel lists, that should be really empty until some scanning was done.

Thank you for advice. Now i know I can delete everything in channels folder.