Each form of will has its own requirements and conditions. As testator, you must comply with the conditions of the form you have chosen, otherwise your will may be invalid. However, a will that does not meet the requirements of one form may be valid as another form.
For example, a will that is intended to be a will made in the presence of witnesses but is not signed by two witnesses may still be valid as a holograph will, if it is entirely written by hand and signed by you.
After your death, if your will and your codicil, if there is one, have not been drawn up before a notary, they must be probated. This must be done by a notary or by the court. The costs will be borne by the succession.
Audio or video recordings of a will have no legal value.