Buying in store is one of the many ways to support an artist. The first thing to remember about buying in store is you can only buy 4 copies per transaction at most. You can do 1-4. Any more than that will not count.
Artists Digital Sales
Artists have started uploading digital singles on their websites and submitting the sales at the end of the week. As of 6/30/23 Billboard will no longer count digital download singles from artist webstores (D2C) towards the Hot 100. Digital Sales will count toward RIAA and certifications in the US.
Buy the CDs and Cassettes from the artist website instead.
Remember buying 10 tracks from the album on your platforms like iTunes, Amazon, Qobuz, & 7Digital can count toward the Billboard Hot 100 and Billboard 200 chart. After buying 10 on iTunes you can click complete album and it'll count as another sale.
This can help each track chart on the Billboard Hot 100.