Openings
First, understand that there is no "best" opening.
However, there are many good, very playable openings, albeit with lots of subjective and (ultimately) inconclusive debate over which are better than others. In choosing an opening the two issues of most concern tend to be not only its objective effectiveness (irrespective of the player's experience or skill level), but also (particularly for lower rated players) how easy vs difficult the opening is to learn and play. These are the essential points addressed by GM Hikaru Nakamura’s “Chess Openings Tier List” series of videos…
Chess Openings Tier Lists – GMHikaru (complete, beginner thru GM)…
https://www.youtube.com/watch?v=M9CwH47r6og&list=PL4KCWZ5Ti2H43-gcoByRnZs5fVR_Lg133&index=4
In the tier lists above, chess openings are classified in terms of their appropriateness vis-a-vis player skill level - i.e., beginner vs intermediate vs GM, etc. For a given player level, the openings are rated and categorized into six "tiers", from "legendary" to "garbage" (the latter being an unfortunate choice of terms, IMO). These qualifiers are used in the context of not only how much so-called "theory" (i.e., documented variations) the particular opening encompasses, but also how tactical versus positional in character it tends to be, which is generally dictated by how "open" versus "closed" the center is at the conclusion of the opening. Openings with less theory to learn and which are primarily tactical in character are generally recommended as an appropriate starting point for less experienced players. So an opening they refer to as "garbage" (i.e. less 'appropriate' - a better term!) for a beginner may in fact be more appropriate for higher rated players who are assumed to possess a more highly developed requisite knowledge base and skills set. For each of the openings discussed note also whether the evaluation is from White's or Black’s perspective.
For beginner-intermediate players check out ‘GothamChess’ (IM Levy Rozman) on YouTube for recommendations and quick exposure to a variety of openings...
https://www.youtube.com/watch?v=NFod-ozimmM&t=103s
https://www.youtube.com/watch?v=Qdyik5UwBtM
https://www.youtube.com/results?search_query=gothamchess+openings
https://www.youtube.com/watch?v=rmbU97iftC8&list=PLBRObSmbZluTpMdP-rUL3bQ5GA8v4dMbT
Chess opening – Wikipedia…
https://en.wikipedia.org/wiki/Chess_opening
Chessable’s Guide to Chess Openings (for White & Black)...
https://www.chessable.com/blog/opening-guide/
Openings Guides – SimplifyChess.com...
https://simplifychess.com/homepage/openings.html
‘Hanging Pawns’ openings videos on YouTube…
https://www.youtube.com/c/HangingPawns
For more on openings fundamentals and principles, as well as specific openings, see...
Chess Openings Resources for Beginners and Beyond...
https://www.chess.com/blog/RussBell/openings-resources-for-beginners-and-beyond
more helpful chess resources, including openings and book recommendations, in my blog...
https://www.chess.com/blog/RussBell
These are some of the best and most respected openings in all of chess:
For white:
- Ruy Lopez
- Italian
- Open Sicilian (English Attack, Richter-Rauzer, etc.)
- Queen's Gambit
For black:
- Sicilian Najdorf
- French
- King's Indian
- Nimzo-Indian
- Queen's Indian
- Grünfeld
- Queen's Gambit Declined
- Slav
- Semi-Slav
Levy Rozman (GothamChess) just says any opening he doesn't like personally is garbage. In his eyes, all the openings he plays are good and all the others are garbage. A lot of the openings he plays and recommends are actually objectively bad. He's literally the worst person to listen to for advice about openings.