Different operating systems have different conventions.
Windows centre- or end-aligns all these buttons (depending on the context), with Cancel last (generally mapping to having the primary action first). That has been its convention since at least the start of Win32 era. If you’re targeting Windows, this is probably what you should do.
Another platform end-aligns all these buttons, with the primary action last.
Still another platform stretches buttons, with the primary action last.
Others have cause to split things, start-aligning any cancel/negative button, and end-aligning others.
If you’re targeting a particular platform, you should generally aim to match its conventions unless you have very good reason not to.
One piece of related reading (and you can easily find others): https://www.nngroup.com/articles/ok-cancel-or-cancel-ok/