Feeling extremely low with no desire left to do anything meaningful, depression is at its peak. No idea when this loop is going to end

I am not enjoying the work i get to do and I am questioning all my life choices I made so far in terms of career especially. I feel like I have made so much wastage of my time and opportunity and how I can get that time or mental energy back. Feels like I have damaged myself gradually with time. I don't feel like doing anything, prep seems super tough in this uncertain job market and so is the application shortlisting rate. I don't feel like doing from scratch anymore but have to , does anyone have any ideas on how this situation can be improved ?