Having entered several of my stories into competitions and also having asked for a critique on the first two chapters of my novel, I've come to realise the importance of how you present your work when submitting it to others. In the UK, there seems to be a fairly standard style of presentation that is expected although always check the presentation and style guidelines when making a submission to be sure that you don't get turned down purely because you haven't followed the rules.
I was no expert on this matter and usually wrote my stories using a favourite font in normal spacing. It wasn't a detail I worried about and yet each time I've come to submit work I've had to transform it into the preferred style.
If you'd like to know more, here's a link to Sue Moorcroft's site. Sue has many published novels, writes regularly for a writing magazine and runs writing workshops both in the UK and in Europe. When seeking help on presenting my work, she is my go-to-guru. Sue Moorcroft's Presentation Guidelines
Hope you find this helpful and wishing you all the very best on your own writing journey.