If you use your own registrar to manage your website DNS and do not point your nameservers to Loclweb you'll need to manually setup your MX records to use email with Google G Suite.
Here are the values for G Suite MX records:
|Name/Host/Alias||Time to Live (TTL*)||Record Type||Priority||Value/Answer/Destination|
|@ or leave blank||3600||MX||1||ASPMX.L.GOOGLE.COM|
|@ or leave blank||3600||MX||5||ALT1.ASPMX.L.GOOGLE.COM|
|@ or leave blank||3600||MX||5||ALT2.ASPMX.L.GOOGLE.COM|
|@ or leave blank||3600||MX||10||ALT3.ASPMX.L.GOOGLE.COM|
|@ or leave blank||3600||MX||10||ALT4.ASPMX.L.GOOGLE.COM|
Every domain registrar has a different way to change MX records. If you don't know how to change yours you can search how to change MX records on XYZ. So, for GoDaddy you would search for "change MX records on GoDaddy."
Here's how to change your name servers on some of the more popular domain registrars: