Automate the addition of email id in a synced table and checking up that emails id in the main table and updating the status

Hi, I want to automate the addition of email id in a synced table and checking up that emails id in the main table and updating the status. This basically means, that there are two tables one of them is a synced table to the main table. There are email ids coming in the synced table through webhooks, I want to automate the next steps that,

once the email id is present in the synced table, the automation should look at that email id in the main table and change the signup status to yes.

It would be great if you guys can help me with this, stuck over it for quite some time. Thanks in advance.