I think it’s very important to have an education no matter how Frum you are. A person has to know what’s going on in the world and many subjects will help you eventually. For example you’ll need maths for a few Mesechtos like Succah and Science will triple your Emunah and awe of Hashem’s creations.
Yes- it’s definitely very important and it’s a great shame not to go to a high school.