Can you attach 2 coaxial leads to a single TV antenna
You need to use a splitter from antenna to two cables. The splitter matches the characteristic impedance of the antenna to each of the coax cables. Tying two cables directly to the antenna screws up the impedance match and can result in signal reflections which severely degrades the signal integrity.

Do note that a 1 to 2 splitter reduces available signal power to each output cable to about half the input signal power. Wider splitters reduce even more. Cascading splitters correspondingly reduces target signal power even more. For example if you cascaded a 1->2 to another 1 -> 2 splitter the signal at the output of the second splitter would be only about one quarter the input power level.

Using splitters is Ok if you have a good strong signal from the antenna. If you are in a weak signal area you should consider using an RF signal distribution device which includes amplification and buffered outputs.