Is a husband considered deceitful and a liar for concealing the true extent of his foot illness before marriage, even though he mentioned it and showed a small model of it?

If the illness does not affect marital enjoyment and there is no fear of it spreading, then there is no obligation to disclose it. So, if your husband's illness is not among those that must be disclosed, he is not considered to have deceived you by concealing it. Nevertheless, it is preferable to disclose every defect to avoid conflict.