Usually legislators make poor executives.
There have been 3 sitting US Senators who have become President in the elected Senate era, two of whom never served in the military.
It’s a reasonable opinion that all 3 were failures, although a lot of people here admire #2 - who did not take control of the Executive Branch and got his brains blown out when he tried.
The main qualification to be elected to the US Senate is being a BS artist. This is a negative qualification for the Presidency.