Looking for a (pref. Male) mc who, over his journey, gains many different classes of power, like mage, archer, teacher, summoner, knight, spearman etc. Or learns a LOOOT of different skills (and preferably uses then more than once..) Something like 'Unlimited Power: Rangers Domain'
Sadly they are the minority cause of how much an author needs to invest in building the system nd world plus characters so sadly very few stay true to this type of genre
Legendary Moonlight Sculptor maybe fits. The MC's class is, well, the title. He usually fights as a swordsman, but he can transform himself to match various sculptures he's created, which can change everything from his class to his race. He becomes all sorts of things, and has entire arcs dedicated to bizarre adventures in other forms. That's probably the closest I can think of to an MC who *actually* does many different things, rather than just the usual mix of maybe learning the sword and magic together, or something.
Growth Cheat is not great but he has many classes at the same time, Library of Heaven’s Path as he progress he learn many different jobs
Overlimit Skill Holder Spoiler The powered people in this story use Skill Orbs to gain skills. Each skill takes up x-amount of "slots" in a person's soul(?) with 10 slots being the max, so most people take 1 or 2 primary skills and whatever minor passive skills they can fit in or can afford. Of course the MC being special with his OP unique Skill Orb that allows him to comprehend any skill he observes being used by others, even passive skills. With enough time observing a skill being used, he can know how to perform the skill too. Thus he collects a variety of skills. And there's more! He can self unslot his special Skill Orb because he saw someone use an unslotting skill to steal a Skill Orb from a victim. So the MC usually goes around without his special Skill Orb slotted (as a precaution against people with a scanning skill) and everyone thinks he's just naturally multi-talented.
Everybody Loves Large Chest on RRL. Spoiler: MC's Classes include Mimic Doppelganger (?) Warlock Archer Wizard Cat ...
I propose "the new world" or "the legend of randily ghosthound" on royal road. I don't think that they learn more than 2 classes at best but the characters grow advancing eith their 'paths'. Each time they lvl up one skill, they gain one point to advance a 'path' and get bonuses the farther they get. So while they have few classes, you should see a lot of skills.
https://www.novelupdates.com/series/moto-sekai-ichi-i-no-sub-chara-ikusei-nikki/ there's no class/job, just skill trees. But there's a lot of them. Though the non-passive ones are basically all attack techniques/magic spells. https://www.novelupdates.com/series/slave-harem-in-the-labyrinth-of-the-other-world-ln/ MC gets lots and lots of Jobs/Classes because getting a Job has requirements & to properly use them you also need to activate them, and basically no one knows how the system work besides MC because he has Appraisal skill... Also he can use EXP gain multiplier boost so he gains levels much faster which makes having many classes much more viable since otherwise he'd get minimal EXP as the EXP is divided between Jobs iirc. Transcendental Mechanic aka The Legendary Mechanic MC gets lots of skills, the system even lets players (and MC who is a Player-NPC hybrid of sorts) get skills from some quests and from beating really powerful enemies etc.. There's the class/job skills you get/can unlock from your main class (there's 5 different base classes which then have different advancement classes to choose from, e.g. MC is a mechanic so he can get mechanic exclusive skills, but the mechanic base class can also advance to Gunner class or Mechanical Martial Artist classes which specialize in guns and close combat respectively. Later there's also specializations within the classes, like the Mechanic class can specialize in Hacking (self explanatory), Armaments (making powerful weapons, mechas, battlecruisers and fortresses those kinds of things), and the Energy specialization is about Energy sources... Besides the main classes there's also auxiliary classes which have their own stat gains and skills, you can technically get as many auxiliary classes as you want, but because increasing your level gets harder and harder the higher your level auxiliary classes are mostly just to get high enough level and powerful to advance your main class. Anyway, there's 1300+ chapters and MC advances his main class at least 8 times, plus a few auxiliary classes, and like I mentioned he'll get extra skills from quests and beating powerful opponents so he gets tons of skills.
Don't remember 'bout multi classes. But as far as gaining lots of skills goes, maybe something like Death March, Ossan VRMMO and/or No Fatigue? Or if it's webtoon then The Gamer?
The Experimental Log of the Crazy Lich Spoiler Chaos Lich King Order Knight Four Elements Swordsman Lord of Friginwinter Messenger of Hell