1... SEO has become expensive, expect to have to pay (WEEKLY or MONTHLY) if you wish to rank in tough niches and / or for tough keywords
2... google releases a lot of updates lately, expect sudden and frequent ranking losses at all times with minimal chances of recovering
3... technical SEO plays a role today that is more important than ever before, so make your site fast, clean, easy to understand and navigate, mobile friendly, error-free
4... if you only follow google's recommendations and guidelines you will never rank, or you will never rank long enough to make money with your site(s), so don't blindly trust google as they are a misleading and deceitful company. Do whatever you need / can to rank, no matter if it's against google's TOS. Even if you break their TOS, the worst that can happen is they remove your site from their index (which will happen anyway at some point if you're a newbie), and you can always start afresh
5... SEO is a long-term game, and a carousel of emotions until you reach the final goal, prepare yourself mentally to accept and overcome any challenge that will inevitably come, or save your money and nerves for something else as SEO is not for everyone anymore
6... if you focus on publishing a lot of content in order to rank start small and slowly, especially if you are using a fresh domain name. It's best to keep publishing 1-2 articles a day for 6-7 months straight than publishing 1000 articles in 1 week and then never do anything for 1 year. If your domain is expired and already has a track record of published content you might be able to get away with more aggressive strategies (ie. publish 20 articles a day), but if your domain is new (as in, LITERALLY new, not new to you because you just registered it) it's best to build it up slowly, like I said (both in terms of content and backlinks)
7... speaking of backlinks, you can't rank without them no matter what anyone (especially google) will tell you. There are people ranking without backlinks, but they're the exception rather than the rule and - while you might happen to be the exception too - at some point you will lose rankings because your competitors - who might not feel as exceptional as you - will need to do something in order to rank and that something that they'll need to do is build backlinks which, in turn, will push you down the SERPs. So, get backlinks to your site as soon as you can. Here's a newbie-friendly guide on what to know about link building to keep your site safe:
https://www.blackhatworld.com/seo/guide-how-many-links-per-day-week-or-month-should-i-build.1502403/
8... never ever EVER make your sites and / or keywords public (not even the niche of your sites) public on this forum... or on any other SEO forum for that matter, but especially not on BHW since this forum is closely monitored by google and as soon as google sees your site and hear that you're building links for your site they will kick you out of their search engine. If this doesn't happen, then other people might (and probably will) steal your niche and keywords when / if they hear that it's so easy and profitable to rank in that niche / for those keywords. If you ever have something to ask and need to reveal stats or things about your site / niche / keywords make sure to blur out / cover all of the important info that can expose your site and / or link it to your GSC / GA / YT accounts. It's nobody business what your site is, or in which niche you operate or what keywords you are targeting, so be as private as you can to enjoy a less stressful SEO journey
9... don't abuse anchor texts. Anchor texts are one of the easiest and most frequent penalties sites incur for newbies because they don't know how important anchor texts are. So, when you build links to your site use as many, and as diverse anchor texts, but never have too much of any type of anchor, especially not too many of EXACT match anchors, these are the most dangerous. I'm not going into details on what anchor texts are or how to use them properly as I don't feel like explaining everything at the moment. And you can google this stuff anyway (or look it up on the forum, I'm pretty sure that it's been mentioned and explained dozens of times in the last few years alone). Just remember not to overuse the sensitive anchors!
10... don't rely only on google! Google still holds the most share of traffic in the world, but in the last 1-2 years people have started getting more traffic from other SEs instead of google, and that's a good thing because google's search engine has gone to shit and in a few years time they probably even won't care about maintaining their search engine anymore, so try to rank in, and get traffic from other sources as much as possible. Also look into social media and UGC sites too, sometimes sites like Pinterest or Reddit are a goldmine for traffic....
11... if you want to keep up with google's whimsical moods (which you should probably do since google - as the bastards they are -they force everyone to play by their idiotic and ultra techy rules) in order to rank you need to become tech-savvy to some extent. You need to familiarize yourself with, and understand things like HTML, robots.txt and htaccess files, schema markups and structured data, semantic SEO / LSI terms / SEO entities, and all that crap. Long gone are the days when SEO was just buy PLR content and publish it unedited on your site and rank in 1 week, nowadays you gotta be a hacker or programmer to rank because google have become a niche thing