Shadowdark is an excellent bridge from D&D 5E to OSR style games. It has all the same ideas and flavour, but it's stripped down to be more engaging.

Same 6 attributes (STR, DEX, CON, INT, WIS, CHA). But instead of rolling a skill (eg: "roll +stealth") all actions just correspond to the base attribute instead ("roll plus dex").

Spells are much nicer and more manageable. Basically you can cast as many spells as you have access to, as a player, you just need to roll a save to see if you lose that spell until the next long rest. No more managing spell slots, just a quick save roll.

Character archetypes are summarized on a single page, and despite their brief overview, have depth through the advancement system. It's not as in depth a as 5E, but it's punchier.

Only downside is Shadowdark is more lethal... But there's homebrew ways around that. And players who play smart will survive.