What you are looking for here is primarily a feedback mechanism issue. This is something that is a hard problem, since good, useful feedback is never quite as simple as just asking someone. Employees are looking for it. Managers are looking for it. Executives are looking for it.
With respect to work time and workload there's always an element of presentism - if "enough" surfaced activity happens over the course of each week and the work is not obviously deficient, then most managers won't ask questions. And you already know that much, since you had many years of school to get that idea in your head. And when it's on-site, it's simple to get to that level - if you're in the office, you're at work, even if it isn't time-on-task.
But there is always going to be a level beyond that, of taking on tasks that are a good combination of "builds up a career" and "builds up the company" - stuff where you can act more independently, and likewise fail independently. You can easily fall into work that does neither or only one of those things, or convince yourself into workaholic behavior and sacrifice everything else. Nobody can offer a clear bright line of "this is the best possible course of action". But there is a "better" out there somewhere!
So if you can measure yourself by whether you did something of both career and company and other life things each day, then you already have a more balanced self-measurement than "quantities of issues" or "lines of code" or "hours in seat".
With respect to work time and workload there's always an element of presentism - if "enough" surfaced activity happens over the course of each week and the work is not obviously deficient, then most managers won't ask questions. And you already know that much, since you had many years of school to get that idea in your head. And when it's on-site, it's simple to get to that level - if you're in the office, you're at work, even if it isn't time-on-task.
But there is always going to be a level beyond that, of taking on tasks that are a good combination of "builds up a career" and "builds up the company" - stuff where you can act more independently, and likewise fail independently. You can easily fall into work that does neither or only one of those things, or convince yourself into workaholic behavior and sacrifice everything else. Nobody can offer a clear bright line of "this is the best possible course of action". But there is a "better" out there somewhere!
So if you can measure yourself by whether you did something of both career and company and other life things each day, then you already have a more balanced self-measurement than "quantities of issues" or "lines of code" or "hours in seat".