Don't forget to proofread your chapters before publishing. Sometimes excitement gets the better of us, and we end up posting with spelling or grammar mistakes. Of course, you can always edit them later, but it's much easier to fix them before publishing than to keep going back repeatedly.
Since you're a new writer, focus mainly on your plot and characters. Try to avoid unnecessary cringe or overused tropes. Make an eye-catching cover because it creates the first impression, and choose a title that's memorable without being too long or cliché.
Keep your chapters at a medium length. I wouldn't recommend extremely long chapters since you're just starting out, but avoid making them too short as well. Around 1,500–2,000 words per chapter works well because it keeps readers engaged and eager for the next update.
If you're an Indian writer, posting chapters around 4–5 PM can help you reach more readers. Also, don't be discouraged if your book doesn't receive as many reads, votes, or comments as you'd hoped. That's completely normal for new writers. Even after writing for more than five years, I still feel disappointed when a chapter doesn't get the response I expected.
Another piece of advice: don't rush to update just because a reader comment, "Update soon!" Writing under pressure can easily lead to writer's block and unnecessary stress. Take your time. Updating every one or two days is a good pace if you can manage it. If you're short on ideas, taking up to a week is perfectly fine. Just try not to make very long gaps between updates, because it can become a habit. Speaking from experience, I once took a month to update a chapter, and now I sometimes struggle with laziness whenever I sit down to write. I'd hate for another writer to fall into that pattern and risk losing their loyal readers.
I think that's all the advice I have for now. If I remember anything else that might help, I'll be happy to share it later.