The C64 always booted to BASIC, specifically CBM BASIC 2.0. There wasn't a provision for automatic booting from disk until at least the C128.

LOAD "*",8,1 was the command to load the first file off of your attached 1541 (if you were lucky enough to have multiple 1541s, your first one would be device 8 and you'd have had to set the device number on others to 9 or higher). Anyone who had and played a lot of games on the C64 back in the day has this command etched in their permanent memory.

There was the convenient-looking RUN/STOP key (yes it is confusing, it's STOP without SHIFT, and RUN with SHIFT held down) but the RUN key would only auto-load from device 1 which was the cassette. Made sense in 1982 when the machine was released because disk drives were about $500 in 1982 dollars, the same price as the system itself.

BASIC 2.0 had no "BLOAD" or "BRUN" to directly load and/or run a binary executable. The underlying Kernal could do this, but BASIC left a LOT of functionality on the C64 unexposed (such as - all the sprites and graphics modes). So the standard was to release programs that were in a form that would look like a BASIC program.

So C64 BASIC doesn't have a BLOAD command but ... it kinda did in a janky way. The ,1 in LOAD"*",8,1 means to "not relocate the file" - and any PRG file on a 1541 disk will have the intended address of the "program" as its first two bytes. If the ,1 is present, BASIC will tell the Kernal to load the file at the address it specifies. (There was no SAVE"xxx",8,1). Some software would load to an address that would overwrite the BASIC main loop vectors and immediately start without having to type RUN afterward. Without the ,1 BASIC will load it into the BASIC program text space at 2048.

Much other software was a hacked BASIC program that had one command, something like 10 SYS 2057 or similar, and then 6502 code right after the necessary codes that told BASIC the end of program text was reached. BASIC program text started at memory location 2048, right after the 1K of screen RAM at 1024. SYS is a command that simply jumps to a machine language program - and in this case, it's jumping to the binary tacked on to the end of the small BASIC program, which would be the game or at least a booting program for the game.

Programs like this had the actual address in the PRG matching what BASIC would want, so LOAD "*",8 or LOAD"*",8,1 typically made no difference unless the game was that auto-RUNing type.

The C64 had 4K of RAM not used for anything else at 49152. It was common for utilities to live there, so you'd load those in with a LOAD"something",8,1 and then SYS 49152 to start them.