Firstly the issue you have with your statement is that when you perform boolean logic (and/or statements here) is that it is evaluated as an expression.
Take the third line in which you have:
if (bolivia == "La Paz" or "Sucre"):
Here you have the boolean logic operator or. This means it will evaluate each side (or rather is will evaluate the first side.. if that is correct it ignores the second statement.. but that is just a tidbit of extra information).
bolvia == "La Paz"
is a valid expression. You are asking if bolvia is equal to the string "La Paz".
"Sucre" is not a valid statement. It has no meaning, you must form this into an expression also.
bolvia == "La Paz" or bolvia == "Sucre" would be two correct expressions that could be evaluated by an or statement.
Now you should have the intended behaviour of your if statement.
I would recommend making this more foolproof also by making it case-insensitive. By this I mean you could change the string into the proper format before testing. This would allow for "sucre", "la paz" and other possibilities.
This would change your initial statement to
bolivia = str(input("Name a capital of Bolivia.")).title()
Now in your test statements you could enter la paz and then receive La Paz as an output.
score = score + 50 can also be shortened to score += 50 as this is a shorthand for the former.
This would change your code to the following:
    score = 0
    bolivia = str(input("Name a capital of Bolivia.")).title()
    if (bolivia == "La Paz" or bolivia == "Sucre"):
        print ("Correct")
        score += 50
        print (score)
    else:
        print ("You/re incorrect")
        input ("Press enter to exit;)")
Hope this helps.