On the top right hand side of the dashboard in the Trader Talent Pro futures trading platform, there is a visual slider displaying in percentage terms how much margin you are using. TIP: Always be aware of how close you are to breaching 100% of your Initial Margin. If you breach this it will constitute a rule break and require a reset to be purchased.
In the below example the trader has 5 lots (futures contracts) of ES
As CME says here "Speculative ("Spec") /non-member initial margin requirements for all products are set at 110% of the maintenance margin requirement for a given product."
and you can see here at the time of writing maintenance margin for ES is $12,000 so initial margin (12,000 x 110%) is $13,200.  5 lots in our example would therefore require 5 x 13200 = $66,000. Which is about 81% of the trader's Venture Tryout $80,000 balance.
If you have traded stocks 'on margin' this is not the same as futures margin, learn more in the short video below from CME (Chicago Mercantile Exchange):