Yeah, it gets weird. First thing I do on every new Mac is disable Spotlight for everything except applications and system preferences, though, and that helps a lot.
Regarding the second point: I really don't get what's up with the start menu search. I don't use Win 10 all that often (secondary OS) and always assumed it's somehow broken for me. I almost never find anything I'm looking for and it feels absolutely ridiculous.
'vsc' will show Visual Studio Code
'vsco' will show a web search of 'vscode extensions' and Visual Studio Code nowhere to be seen
'xc' will show Xcode
'xco' will show Xcode Server Builder