If something is put on a particular footing, it is defined, established, or changed in a particular way, often so that it is able to develop or exist successfully.
basis
The new law will put official corruption on the same legal footing as treason.
新法律将把职务腐败视同叛国罪。
If you are on a particular kind of footing with someone, you have that kind of relationship with them.
They decided to put their relationship on a more formal footing.
他们决定建立更正式的关系。
You refer to your footing when you are referring to your position and how securely your feet are placed on the ground. For example, if you lose your footing, your feet slip and you fall.
He was cautious of his footing, wary of the edge.
他小心翼翼地站稳,生怕从边缘掉下去。