Can u take folic acid tablets and multi vitamins tablet containing folic acid each day? Is that over dosing?

Depends. Dose depends on the condition being treated (anemia, sprue, pregnancy). Generally a total intake more than 1 (one) mg a day is associated with a higher incidence of side effects like loss of appetite, nausea, gas, abd pain, irritability, etc. Check with your fp if you have further questions about safe amount of folic acid.
1000 micrograms. Is the upper limit for people 19+ years old [1000 micrograms=100 milligrams. Double check the units on your bottles]. Generally you pee out what you don't need. Much higher doses of folate (folic acid) are sometimes used to treat/prevent certain conditions. It's great that you're checking in and being careful about what you take. Here's to your health!