Here's how you can improve your proficiency in structural modeling and simulation.

To improve your proficiency in structural modeling and simulation, regularly practice with advanced software, stay updated with the latest industry trends and techniques, seek mentorship from experienced professionals, and continuously engage in relevant training and certification programs.

Beyond the necessary engineering knowledge (continuum, solid and structural mechanics; materials' behaviour; beams and plates models and theories; etc), it is extremely important to also have a grasp on the numerical method you are using (discretization/meshing; elements and basic equations; solvers and convergence criteria;etc). If the first allows you to understand and decide what you need to model and simulate,the latter allows you to properly understand how you can "explain" it to a software,assess what results you can expect, and to troubleshoot issues, may them be physical or numerical. For Finite Element Method I suggest reading "Finite Element Analysis for Engineers - A Primer", by T.K. Hellen & A.A. Becker, published by NAFEMS.

If you are in your career's early stages, I suggest you invest more time in understanding what it's "under the hood" of a software rather than mastering the ins and outs of a specific one. In fact, each industry has their preferred softwares with its pros and cons. And each company tends to have a preference over competing products. It may very well be that changing jobs could lead to changing softwares. If you are solid on your theoretical basis and engineering knowledge, picking up a new software in a short time will pose no issues. And this will give you more value and freedom as an engineer. Mastering a software comes with time and usage, and by naturally facing issues you will need to solve in your daily duties.

If you can't engage in practical projects through internships or collaborative projects, it is always a nice exercise to try to repeat the tutorials, and later tweak and change some options and decisions to assess what changes, how and why. Practice and experience will be extremely more valuable if you really understand what you are doing and why you are doing it, so always face everything with critical thinking and a curious mind. An entry barrier on practice in structural simulation is actually having the software license. If you do not have a software license, you can try to contact your faculty or even software houses for a demo version. Or you could consider one of the various opensource and free solutions around.

I will never stress enough the importance of a healthy and functioning feedback loop. It's the basis of improvement. However, sometimes and in some situations a proper feedback loop is not in place or not applicable. In those cases. you can still improve by giving yourself feedback. This can be done,for example,by analysing different methods or routes you could have undertaken for solving your problem. Could you have used a different approach? Could you have divided the complex model in smaller and easier models and reach comparable results? If not, why? With critical thinking and creativity, you can always find ways to improve. However, four eyes are always better than two, and worse than six. If possible, always ask for feedback.