Neither “Don’t miss out on these teacher” nor “Don’t miss out these teacher” are quite correct. “These” is only used with plural nouns, so “these teachers” but “this teacher.” Regarding the expression “to miss out (on),” it is necessary to include the “on” when you immediately follow it with what one would be depriving oneself of - so: “This is a great opportunity, and I don’t want you to miss out”, but “This is a great opportunity, and I don’t want you to miss out on it.” “On” would also be added in a compound sentence in which the relative prounoun connecting the two separate sentences refers to the thing that one would be depriving oneself of, so: “This is a great opportunity that I don’t want you to miss out on.” Back to your original sentence: “Don’t miss out on this teacher” (if you are talking about only one teacher), and “Don’t miss out on these teachers” (if you are talking about more than one) Cheers! P.

"Miss out" is a phrasal verb. When used with an object, "out" is followed by "on." Don't miss out on these teachers (teachers not teacher because "these" is plural). "Don't miss out these teachers" is incorrect.

No revise bien lo que escribí y omití pluralizar la palabra teacher.