Accounts suspended following a third strike will not be able to run any ads or create new content unless the suspension is successfully appealed.
To reopen your Google Ads account, you must first know the reason behind such suspension.
Here is how to check the appeal status: Click the tool icon in the upper right corner of your account. This email scam states that the recipient's Google Ads account is temporarily suspended due to "circumventing policy violation".
I actually just got my Google Ads account suspended because I forgot to update my billing address before adding a new card. If you make a mistake, there is no warning system and no appeals process.