malloc is just a C api, it’s not a syscall, and Linux is no different.
malloc/free on Linux is probably using mmap under the hood, and doing some bookkeeping to decide when to decommit memory to give it back to the OS.
You said "they invented 15 ways instead of having malloc". By "they" you mean Microsoft right?
Windows does have malloc as a C api for programs using the C runtime library. Same as everywhere else.
Then, at the OS api level, there are indeed several memory management functions. But you usually don’t need them. Except if you are writing a custom memory allocator for instance. Also same as everywhere else.
So saying Windows has X memory management functions instead of malloc is incorrect.