Update first_problems.md

docs/level_0/first_problems.md

@@ -1,5 +1,5 @@
 # First Problems
-- PRINT_START Issue - "Extruder not hot enough" and other problems that come as a result of a problematic PRINT_START macro
+- [PRINT_START](https://github.com/500Foods/WelcomeToTroodon/blob/main/macros/PRINT_START.md) Issue - "Extruder not hot enough" and other problems that come as a result of a problematic PRINT_START macro
 - X-EndStop Issue - The X-Endstop on the toolhead might not be getting tripped when expected
 - Bed Placement - Moving the bed forward or backward if it isn't positioned properly
 - Hitting the Doors - Adjust the limits in printer.cfg to prevent this from happening