Entering university consumes a lot of time and money. There are ways to receive university education at a lower cost. You can try it first.
First, MOOC (Massive Open Online Course) is a way to take lectures online. The specific composition depends on the service and lecture, but in many cases, it repeats “watching movies of the lecture” and “answering quiz about contents of the lecture.” It is a structure similar to the tutorial that achieves small goals in order. If you prefer contents in Japanese, for example, you can watch classes of Open University of Japan founded in 1981 with free of charge. Alternatively, many universities and research institutes hold public lectures.
Many universities prepare easy-to-participate systems such as ”auditorium” or ”course student”. Some universities are positive in accepting postgraduate students. Those universities adopt a system that makes it easier for full-time workers to learn, such as doing classes on weekends or weekdays evenings. As a concrete example, I was a student of the course of technology management on Tokyo Institute of Technology for 3.5 years. In the daytime I worked in Cybozu and then take lectures on evening and weekends.
If you are not interested in degrees, you can take lessons as auditors. If you aim to take a degree, you can take classes gradually, and then get admission as a regular student to get a degree. I have attended the classes of Seikei University law school from April 2018.