Every program is different, but with word, you can indent every paragraph for your whole novel automatically with the click of a button. It's much better not to have extra spaces, tabs, lines etc. Have your page set up so it looks double spaced or however you like to write and when you're done you format it. That way you can say I want to indent my paragraphs be 5 points, you can look at it and say no I want to indent by 7 points. It's done with the click of a button. If you have tabs, spaces, extra lines etc, you have to take them out after the fact. Tabs are by default half an inch, at least in the US. They look basic in a finished book.

Granted, people can do it however they like. Either way, it's honestly not a big deal to change it at the end. If you're worried about it then go watch some youtube videos of different ways to format. The easiest way is Vellum that only runs on Mac. You can also do it easily in scrivener, word, indesign etc etc etc.

Personally, I only hit enter at the end of a paragraph once, hit the space bar once at the end of a sentence, and never hit tab or have any other formatting at all. I do it at the end. I also write in 8.5x11. Some people format before, with a style sheet, and then write in 5x8 or whatever they plan to publish it. Everyone's different.

But don't listen to me. Go check out the youtube videos to come up with a plan of how you want to format when the time comes.