Here are the steps you need to follow to install a door:
1. Remove the old door and frame.
2. Measure and level the rough opening.
3. Check the sill.
4. Adjust the jamb according to the measurement you took.
5. Secure the frame with shims.
6. Screw the frame into place.
7. Set the door in place and test it.
8. Fit the trim and finish up.
I hope this helps! Let me know if you have any other questions or if there is anything else I can help you with.
[Here](https://www.wcmanet.org/door-installation/) is a link to a step-by-step guide on how to install a door that you might find helpful.
