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Black holes definitely have mass, which is calculated by the observations of motion of celestial bodies.
Indeed, Newton's 3rd law is 'equal and opposite forces.' so to stand up you need to exert a force upon the Earth at least equal to the force of it pulling upon you.
For instance, you Don, exert an extremely tiny gravitational 'force' upon the Earth and even the people around you and every object around you and even objects on the other side of the planet. Even the moon! And the planets and sun and so forth.
Newtons basic gravity equation defines force(F) equal to the gravitational constant (G) multipled by mass1(M) * mass2(m) divided by the radius(r) squared.
F = GMm/r²
Where G equals 6.67430 × 10^-11 m³ kg^-1 s^-2
Hope that helps.