You are working hard for the SEO of your website. But How can you do SEO check to see what you have done so far is correct or need more work or even it is not correct? There are many free and paid services that you can use. Also there are many browser plugins as well such as SEO Doctor.
Free SEO check services provide you limited information but for a start up web site that does not have so many pages, they will provide quite informative information like SEOBILITY.
For WordPress users, there are numerous SEO plugins that guide you to fix your errors. But, make sure your WordPress SEO plugin is fully compatible with your theme. Some SEO plugins are not and give you false info. For example, You have inserted an image, added alt text to it, but your SEO plugin says there is no image with this page or post or alt text is missing.
Some of the WordPress themes are not SEO friendly, even though they may look very nice. In such case, you must change your theme.
Make sure your custom coded website is SEO friendly in the code part or at least you have an available developer to make the required changes and updates for you.