A paint can forge is a great first forge to figure out of blacksmithing is for you. It is inexpensive to make and will work for small projects. You can use a propane torch to heat. It will be too small to work medium and larger sized pieces of metal.
The short answer is no, you should not forge your first knife from a lawnmower blade. Instead of using a found lawnmower blade, use 5160, 1084, or 1070. I will go over the reasons in this article, along with other basic blacksmithing tips.
A tutorial on building a charcoal blacksmith forge from an old propane grill. We will make a simple pipe tuyere forge from a discarded grill, a metal fence post, and a few inexpensive materials.
An explanation of the fuels you can use for your forge, focusing on the pros and cons of, and which is right for you. Charcoal, coal, or propane, plus an often overlooked alternative, induction.
DIY step by step instructions for restoring and refinishing metal projects
How to make a basic welding table from rebar steel and used bed-frame metal.