To use an NSP file, you must have a Switch console running Custom Firmware (CFW). You would typically use a tool like DBI or Tinfoil to install the file once all "parts" of the RAR archive have been merged and extracted.
A well-known community site that hosts digital backups and homebrew-related files. NBA23-(USA)-NSwTcH-[BASE]-NSP-Ziperto.part2.rar
While the Switch version offers the full "MyCAREER" experience, it runs at 30 FPS compared to the 60 FPS found on more powerful consoles. You can view direct feed gameplay of the Switch version on YouTube to see the visual trade-offs. To use an NSP file, you must have