I am currently a 3rd year student. I have however interrupted my studies recently because I felt like I wasn't going to be able to do well in my exams, and I was struggling to do my final year report. An interruption means that you basically stop your degree wherever you're at, so for me it's basically towards the end of this semester, and then come back after an agreed period of time to continue with your studies. I will be coming back in September to redo all my lectures from scratch for this year etc, and hopefully keep working consistently from the start all the way to the end. My depression got particularly bad around Christmas time, so end of the first semester and start of the second. I guess I ended up in a similar situation to you where I missed a lot of my lectures from my last semester and felt like I will not be able to revise enough for exams, especially because I couldn't get myself to start working.
You might want to look into interrupting, though bear in mind that it might be past the deadline already (for my university it's tomorrow, 22 April) and you need to get permission from your department as well. It may also not work out the same way it does for me; the people in my department were quiet forgiving and pretty much let me not finish my report despite applying for the interruption after the deadline, I was simply told to put the last day of attendance as the due date so it would look as if I interrupted before the report was due. My department also allows for me to pretty much resit the entire year (Even though we had homework that was part of the assessment for the modules, I will be able to redo those. Except for one module that was report based and I had already completely finished it in January, but any other module that I haven't handed reports in/written exams for I am allowed to redo completely)