Statement I: H₂ molecule is more stable than HeH molecule.
Statement II : H₂ molecule has lower bond order than HeH molecule.

H₂-(σ_1s)²
$\mathrm{B}·\mathrm{O}=\frac{2-0}{2}=1$

HeH (a Hypothetical molecule)
Number of electrons in HeH = 3
$\mathrm{HeH}-{\left({\mathrm{\sigma }}_{1\mathrm{s}}\right)}^2{\left({\mathrm{\sigma }}_{1\mathrm{s}}^{*}\right)}^1$

$\mathrm{B}.\mathrm{O}=\frac{2-1}{2}=0.5$
B.O in H₂ > HeH
Bond order $\propto$ Bond energy $\propto$Stability
I is true II is false.