Viewing the budget pacing details can be achieved by setting a target budget at either the account level or a set of campaigns.  

Account-level target budget pacing for each Google Ads account can be managed within the account dashboard using the section shown below:

You can optionally choose to receive alerts when the spend is approaching the target amount and/or set a rule for pausing your campaigns automatically and re-enabling them at the beginning of next month.

Campaign level target budget pacing, alerts, and actions can be managed from within the same screen as the above:

The budget pacing info can be seen in the account list overview screen as well as the  main alerts dashboard