Here is my code below. You can change the values for the total health and the length of the bar and it should still work.

from math import ceil

total_health = 100
health = int(input("input health 1-" + str(total_health) + ":"))
brb = "x"
other_brb = "-"

length_bar = 10
#multiply x to represent hp
hp = ceil(health / total_health * length_bar)
bar = brb * hp
end_bar = other_brb * (length_bar - hp)
#add bars together
print(bar + end_bar)

This is what I changed in your code:

• I used ceil( ) to round up the number so the bar shows at least one mark until health is zero. You can use round( ) instead if you want, it's up to you.
• You can make the bar as long as you want by changing the value for length_bar
• To calculate how many * to print, I did hp = ceil(health / total_health * length_bar). Think of health / total_health being the ratio.

I noticed in the example you use %. Modulus gives the remainder, not the quotient. Use / for division. Have a nice day, I hoped I helped (: