Beginners should play like they did in the 18th and 19th century = open games with 1.e4 e5 2.Nf3 (or 2.Nc3 or 2.f4) 2...Nc6 3.Bc4/3.Bb5/3.Nc3 etc. If they meet 1.d4 they should answer with 1...d5.
London is a great opening, but not for beginners. London is for players who do not have ambitions of improving and just want a solid and easy to play opening.
As you know I already have a post related to this but for intermediate players. (If you haven't read it you can post here: Can anyone tell me which opening is the best for intermediate players?
So you have to do the same but for beginner players.
Example: London
Advantage: Easy Middle Game strategy
Disadvantage: This opening has a bad reputation
Thank you 😊