Students in their first year of computer science (CS1) at universities typically struggle to grasp programming concepts. This paper covers research using a Java programming language-guided visual execution environment (VEE) to teach CS1 students about programming concepts. The topics covered include input and output, conditionals, loops, functions, arrays, recursion, and files, all of which are covered in an introductory programming course. The VEE walks beginner programmers through the fundamentals of programming, utilizing visual metaphors to explain and direct interactive Java tasks. The primary goal of this study is to determine whether a cohort of 105 CS1 students from four different groups who are enrolled in two universities—one in Madrid, Spain, and the other in Galway, Ireland—can advance their programming abilities under the guidance of the VEE. Second, does the improvement vary depending on the programming concept? The findings demonstrate that students' programming knowledge has greatly increased. This improvement is significant for all programming concepts, while it is more pronounced for some topics than others, such as operators, conditionals, and loops. Additionally, it demonstrates that students had little prior understanding of files and recursion. The most well-known concept to them was the sequence concept.