There are two provisions in the Constitution for its suspension.
one is an amendment declaring the constitution suspended, although such an amendment itself might be unconstitutional.
Second, a Convention of the States, where a new constitution is voted upon and placed in stead of the current constitution.
Contrary to popular belief, there are zero provisions in the Constitution for martial law.
Zero, zilch, nada. And even fewer for the legislature to grant such broad powers to the executive. Nope, not there.
Zero, zilch, nada.
Before we begin to argue the scope of such powers, let’s agree that each time martial law has been declared in the US (seven times), it was an unconstitutional power grab and any future declarations of martial law will be similarly outside of the Constitution.