There are two sides that a fresh business should focus on.
SEO
Optimizing the website (content) to meet the Google standards is not difficult, especially with easily available website templates, built for speed and already tweaked to match your needs.
Basically, choosing a platform and sticking to it. For example, after installing Wordpress, you can use some free templates or go for a paid one instead.
The difficulty is technical wise: making sure that any tweaks you do are spotted and ammended quickly by the Google search bot. It's not just a matter of creating a website and posting content, it's a matter of pointing to Google with 'your finger', that your website is here, and it's about xyz niche, etc.
SEM
The other side of the coin, pointing to potential customers that your website/product meets all their needs, in order for them to buy from you instead.
This requires an initial amount of money to pay any advertising efforts on Facebook Advertising, G. Adwords, etc.
Competition is aggressive, so are bidding prices. If you want to stay competitive, you'll pay the right bid and track your advertising projects like a bloodhound.
Right now, SEO is a child's play, with many services also offering you some interesting packages, and some link building on the side. The issue with link building is not falling for the old "private network links" scam (method still functions, but can ruin your online business if identified by algorithms), and instead focus on the user retention, via a smart and professional template/UI, and a constant engagement with the potential buyers, through social media interaction.
The aim is the same: maintain a clean brand, with a clean linking profile, and 'outpacing' the competition in terms of user experience.
And after all you've achieved, you're still not done, think of ways to improve your product/website, make it an evergreen thing, something that nowadays and future users alike will appreciate everytime.
Your ultimate target is the user, not the (search) bot.
