You may need a permit and meet their requirements. You can buy all the parts you need at Lowe's or Home Depot, many already cut. Pay attention during the permit process to height, width, railing requirements.
Agree with Cynthia. I would apply something like this https://amzn.to/39M9GqY though at least to the front of the step to make sure its not slippery when wet. Treated lumber, which is what it should be made from, will be slippery when wet for several years until it ages.
It probably won’t need permits, if it is limited to 2 risers and 3 treads, unless you are in a litigious State. Look at your local City or County’s free on-line or paper Hand Out For Deck/Balcony Construction requirements.
It will show you how to build the stair carriage, treads & handrail.
Yes, coefficient of friction is important.
Your time is worth something and I suggest buying exterior “treated” building materials.
Here's a post that might help - http://modularhomeblog.com/diy/mobile-home-steps.html
Mobile home stairs are similar to any stairs. A platform just below the door will help the exit and entrance.
If you aren't really good at drawing them out, I would recommend buying pre-cut stringers, treads, and hurricane ties. Then you screw the ties onto the stringers and attach to the entrance. Treads are screwed onto the stringers. You can get them at any big box home improvement stores. The treads are ridged for extra traction. I prefer them over plain boards.
This might help. https://www.hunker.com/13416338/how-to-build-wooden-steps-for-mobile-homes
Hi Kim, here are a couple of ideas that may help you,