what opening to advise for a beginner?

Agreed with #2. Italian (the sharp lines with c3 and d4) was my first white opening i learned from a Pachmann book as a beginner.



is a main line. Explain to him what happens when black plays something different. Eg. the variations 4...d6?! 5.d4 exd4 6.cxd4 Bb4+ 7.Kf1! and 8...Nxc3?! 9.bxc3 Bxc3? 10.Ba3!

I learned a lot about how to play in open games with these opening lines.

I chose my repertoire after exploring various openings.... I discovered that I was most comfortable playing closed games.. (slow and steady they say... but that doesn't mean that there are no bumps hehe...).... I'll advise you just teach the basic principles and let the student play by themselves not knowing any opening in particular ( I and my friends started out this way ...hell even Leela and Stockfish did same.. without any opening books)... It really helps one to understand "why" this move had to be made...
After some weeks .. probably months and series of games... Then you can teach the individual the different systems.. show the individual openings with e4... He/She should try them out for sometime... then you can move to d4... c4... Nf3.... After the individual explores all... with experience the individual will find the opening that seems most comfortable....

Ah while writing this I just remembered that was also how Mr. Shaibal from "The Queen's Gambit" taught Beth Harmon how to play.... cool eh?

Kings pawn opening

IMHO
As White: London system or Queen's Gambit
As Black : French Defense against 1.e4
King's Indian Defense against 1.d4
All these are solid and easy to learn. They can be played against almost anything. And they give you a entryway to a good middle game with some sharp tactics.
As a beginner I did not want to get bogged down with all the opening theory involved with the Ruy Lopez, Italian game or the Sicilian on move 3.

@pekfjkcddd
When you meet e4, play petroff trap, it works on titled players.

I recommend that you follow opening principles for now

You should start by learning endgames. It is more important than openings.
Knowing the opening principles is enough

aS black play 1 e4 e5 and 1 d4 d5, as white play 1 e4

The four knights game as white and Berlin defense against e4 should be good enough.

You can survey different openings at chessopenings.com. National master Dereque Kelley provides concise information on approximately 20 different openings and defenses, from the Alekhine Defense to the Vienna Game, covering the pros and cons for both white and black.