All I can give you is three main tips that I've faced during these past few weeks writting up chapters.
1) Plan out everything you can. Characters, traits, plot, premise, direction, and your style.
2) Find your own voice, write what you want to write not what others want to read. Take criticism to heart but don't butcher your work for the sake of pleasing audience.
3) Edit twice or more, maybe once after you wrote the chapter and once after a week or so.
4) Brush up on your grammar. It will save you lots of time during editing.
These are generally good tips, but they can be refined further for more effective use. Especially the first one which I take the most issue with.
1) Plan out everything you can. Characters, traits, plot, premise, direction, and your style.
Planning is good, but it can also parallelize you and make you never wind up starting in the first place. So, when it comes to planning you do have to do some prioritizing. There is also something missing from the list, that is your world's lore. This can range from "It's the real world, but this location in the real world has this kind of history and background." to the entire magic system, history, and geography of the fantasy or alien world your story is based in.
I would prioritize the items from the list, plus the lore as I just said, as follows.
1) Lore and premise.
These are the two most important things on the list. You want to have a VERY good idea of your lore and premise. This is the foundation of the story, and this goes double if you want to skimp on the other items further down the list. Even if the rest of the items are almost completely ignored, having a strong lore and premise will be a firm foundation that allows you as the writer to improvise and figure out where those other things need to be while you are writing.
You can never go back and fix your lore and premise once you bungle them, but almost everything else can be explored and fooled around a little bit with as you are trying to find your feet.
2. Characters.
Good strong characterization is what sells the story for your readers, it is extremely important. While you are making a character, character traits and personality are minor factors. The thing you REALLY want to focus on is what professional story tellers call a "character spine." A character spine is the one thing you can sum up in a single sentence that best describes your character's motivation in life. The character spine is the thing that drives and defines all of your character's actions throughout the story. Everything else just flows from that.
Aside from coming up with some idea of the character spine, the other thing I would recommend is get some experience in role play. Role play is the best place to learn how to wing it with a character. Having to improv due to your one character being the only thing under your control and having to respond to other people who are controling their own characters will challenge you more and force you to pay a lot more attention to what defines and motivates your character.
3. Style.
This goes into finding your own voice. You need to have your own voice in your writing in order to make a compelling story. The lore and premise are the body and bones of your story. The characters are the heart and blood of the story. Your style could be said to be the soul of the story. It is etherial and hard to define half the time, but without a good sense of defined style your story just feels dead, especially in regards to the more definable things like chapter length, perspective, and defining writing characteristics which will make your story a total mess if you are inconsistent with your style in regards to those things.
4. Plot and direction.
These are important, but just starting your story is more important. Remember, web novels are kinda like your rough draft. This allows you to just start without having pre-planned your plot and direction. You can find those later. (Just... you DO actually have to find them at some point, the sooner the better.) It is entirely possible to edit later in order to fix an early lack of plot and direction so long as the rest of your work is good.
5. Character traits.
Your character spine, as mentioned in #2, is very VERY important. However, simple surface level character traits, while they can be endearing, are so unimportant that you could decide to just not think about them at all. In fact, I would actually recommend against planning character traits. Allow them to develop on their own as a result of the character spine. If you have a well constructed spine for the character, good traits should pop up on their own while you are in the middle of writing.