While it may not be ideal, it is possible to have a gap in your educational timeline. The level of flexibility regarding gaps depends on the university and the degree program you are interested in.
If the gap occurs between high school and an undergraduate degree (Bachelor’s), it might raise some concerns as there could be uncertainties about the reasons for such a large gap. However, if the gap is between an undergraduate degree (Bachelor’s) and a postgraduate degree (Master’s or Ph.D.), it is generally not problematic. Providing a clear CV with details of your activities during the gap period can help address any potential issues.
Typically, gaps of less than 3 years are not considered significant, but a gap of over 3 years may be seen as substantial and may require clarification.
Overall, it is best to check with the specific university you are applying to for their policy on gaps in education and how they assess such situations.