Hi Koyea. Walter here from microDev (Shopify Partner).
Unfortunately, your questions is a bit of an ambiguous one as it really depends on where YOU want your email link to be. If you post a picture of where you would like to place your email address on your home page, then I’ll gladly let you know where you can add the code. Otherwise, please feel free to contact me on firstname.lastname@example.org for more help with this or any other customisations you may want to do to your website!