what are the basic Mac startup key combinations

It occurs to me that maybe you're asking about these key combinations to be used if/when you are having some problem starting up your Mac: Startup key combinations - Apple Support

If you are not having trouble with your Mac, then these key combos are best left alone as the utilities and access can easily be misused and cause real headaches.

If you could elaborate on your question then we fellow users can more easily point you in the direction of the answers that will help you best.

D.I. Johnson wrote:

It occurs to me that maybe you're asking about these key combinations to be used if/when you are having some problem starting up your Mac: Startup key combinations - Apple Support

If you are not having trouble with your Mac, then these key combos are best left alone as the utilities and access can easily be misused and cause real headaches.

If you could elaborate on your question then we fellow users can more easily point you in the direction of the answers that will help you best.

Very perceptive suggestion!

What do you mean by "basic opening strokes"?

You don't say which Mac you have. Start here:

Mac - Official Apple Support

Select your model, for example MacBook Pro and click on that. You'll be taken to a great page with resources for setting up and using your Mac.

MacBook Pro - Official Apple Support

These links will get you started.

• Set up your iMac for new Mac users – Apple Support

• Set up your iMac – Apple Support

• When you’re done setting up your iMac – Apple Support

• macOS User Guide - Get started with your Mac - Apple Support

Do you mean keystrokes for keyboard shortcuts?

https://www.makeuseof.com/windows-vs-mac-shortcuts/

I didn't go there initially because "new computer first Mac" sounds like the OP just needs normal learning curve type info. I hope they don't already need to use these startup key combos. 🫤

We both had the same thought (though you paid better attention to the sub-forum!). Hopefully, the OP will either answer back with clarifications or has the information they need.