I'll see what I can dig up? I learnt it as a second language at school, so I don't have many handy resources for self-learning. I was thinking of adapting some resources I used for tutoring 101 Chinese into a small intro for HB, but I need to de-identify all the materials and write out the verbal stuff into text, so may take a while.

The problem with learning Chinese online on your own as an adult is that there are too many resources out there and not too few, and lots of shills and people promising you 'one-stop-shops'. In reality you're going to need a diversity of resources including video, text, language partners and, ideally, some formal tutoring. A tutor is the only thing I'd pay for, if you so choose and can afford it, because most stuff you should be able to find for free.

Essential resources are:

1. Pleco dictionary (the best dictionary by far)
2. Chinese Grammar Wiki
3. WeChat (for adding friends you make). XHS could be a decent compliment or substitute. I've only started reusing it because of the sudden spike in interest, but I'm not huge on social media so can't say precisely how to use it for learning Chinese yet.

Your first and most productive starting point is to learn Pinyin. It is the most popular romanisation of Mandarin sounds into latin letters, then mapped onto characters. Most sounds will be shared with English, but you will need to learn some new sounds and not be misled by the fact that they share the same letters in English. For example the 'c' sound isn't an s or a k, it's more like a 'ts' like in the word 'cats'. The X in xi jinping isn't a 'ks' or a 'zhhh', it's closest to a 'shh' but with a slightly different tongue placement. I don't want to scare you off but if you use the English equivalents you'll be 80% there.

Tones are tricky, I don't want to get into them here because you'll need to learn them early but won't get a proper handle on them until later. You'll learn them in a basic form early on as the 'four tones', until you learn about melding tones (sandhi) later on, but don't worry all in good time. Push ahead after you've roughly got the four major tones comfortably within your regular pitch variance.

The Chinese grammar wiki would be a good substitute for a textbook, but there are probably PDFs of textbooks you can find online. Find one that's tied to the HSK system and work with that, because it's mostly standarised and will teach you Chinese closest to what's used in mainland China.

Optional resources 4) HelloTalk or iTalki or equivalent (or whatever is the current version of those apps) 5) MeetUp (or equivalent where you live)

The optional resources are for finding an online or offline language exchange partner or group respectively. If you haven't had one before, it's a mutual learning agreement to support one another in learning the other's language(s) usually broken down into 50/50 time for bilingual exchange. I say that these are optional resources in the early stages because you cannot rely or expect your language partners at this stage to be able to teach you basic grammar. They're more opportunities to try out what you've learnt formally and make language fumbles in a safe(r) environment.

In the early stages it will more be about learning set phrases, basic words and some grammatical things like sentence order and particles to mark tense, but the proper stuff is on you unless you luck out and find someone who's both able and willing to teach grammar. Otherwise yeah it's textbooks or tutors.

If you have a website in your area for finding tutors, you may be able to find someone who's able to tutor you in Chinese for a price you can afford, this often includes students in Teaching Chinese as an Acquired Language who are practicing in advance getting their qualifications.

Exercises/drills

5. iqiyi
6. Bilibili

Consuming Chinese language media (subtitled) will help tune your ear and you may be able to start to pick up on words you've learnt and start to learn tones. Early on try to watch the kind of shows you'd normally watch in your primary language(s) so you don't get bored (that being said, you may find new genres or subject matter that you've never encountered before). Another way of doing this is watching Chinese dubs of shows you've already watched and enjoyed, since you may already know the plot, so the new words fall into place. Don't feel bad about pausing or rewinding the show to jot down new words you hear.

A good exercise is 'shadowing'. Basically you watch or listen to a show and try to repeat what they say as closely and quickly as possible, even if you don't understand. You'll pick up on pronunciation, accents and tonal patterns. However this can result in people adapting awkward accents so don't use it as a method of imprinting someone's accent onto your own, just follow along in your comfortable vocal range.

You won't need to learn how to handwrite characters nowadays since you'll mostly be typing pinyin, but if you want tips on that then I can draft something up too.

I don't wanna type too much because I think the most important part is to start /somewhere/ because you'll never find the perfect resource that will do it all for you. It's best to at least get the ball rolling with /something/ because you can always go back and tune up your tones or characters or pronunciation later down the track. Happy learning!