I use an app called “Duolingo” to take daily quick lessons, and a website called “iTalki” to hire a teacher to give me daily classes. There is another app challed “Du Chinese” which has almost daily new Chinese stories and you can bookmark words you don’t know and they have spaced repetition decks which are awesome to memorize.
Duolingo is free (although the ads are annoying).
Italki you pay by the hour, some teachers charge as low as $5 an hour but some go over $10 an hour.
Du Chinese is free but some stories series have to be paid to unlock, like you can read the first one but the rest is locked for premium, never bothered me though.