Would it be possible to "ignore" the extra commands in a macro?

Would it be possible to “ignore” the extra commands in a macro? For example, if in a macro one of the commands were “Select Tracks” and the parameters were First Track: 3, Track Count: 1, and Mode: Set or (Mode=“Set” Track=“3” TrackCount=“1”), and it was applied to a project with only 2 tracks, is there any way that Audacity could “ignore” this command?
I’m using Windows 10 and I’m using Audacity 3.0.0.

The problem isn’t the “Select Tracks” command - that will simply select nothing.
The problem is (probably) that the next command in your macro requires an audio selection, and you don’t have an audio selection.

Macros don’t do “conditional statements”. You can’t say “if then do ”
Macros are a simple list of commands that runs from top to bottom.

To run commands conditionally, you need to use a proper programming language, such as “Nyquist”.
See: Nyquist-Macros - Audacity Manual

Thank you! How do you make a conditional command in Nyquist?

Nyquist is an extension of the XLISP language (XLisp)

There are several conditional statements available. Probably the most common is “IF”.

(if test-expr
   then-expr
   else-expr)

https://www.audacity-forum.de/download/edgar/nyquist/nyquist-doc/xlisp/xlisp-ref/xlisp-ref-137.htm

There’s also “when”, “unless”, “cond”, and “case”.

These are collectively known as “control structures” (https://www.audacity-forum.de/download/edgar/nyquist/nyquist-doc/xlisp/xlisp-man/xlisp-man-019.htm)

Here’s a loop structure that you could try in the Nyquist Prompt effect:

(dolist (trk (aud-get-info "Tracks"))
  (print (assoc 'name trk)))