I was told im unable to become pregnant because I had an abortion. Is that true?

Mostly No. Unless the abortion was traumatic which resulted in damage to your reproductive organs, there should be no problems in terms of you getting pregnant. If you are concerned that there might be damage to your reproductive organs, please contact your ob/gyn and get checked out.
No. The only concern is that you could have adhesions or an infection after the procedure. The majority of patients have no major problems. However, if you fail to get pregnant after 6 months, you might ask to have your ob/gyn do simple tests to evaluate your fertility.
Usually not. The majority of women that have an abortion are able to get pregnant in the future. There are rare cases where severe scarring in the uterus (womb) can happen after an abortion that may make it difficult or unlikely for a woman to get pregnant again.
Maybe. If the abortion was performed in a way that caused adhesions or scar tissue in the uterus then those adhesions (synechea) could prevent pregnancy. However most abortions should have no effect on future conception.
Probably not. Unless you had a significant complication from the abortion such as a severe infection, abortion does not cause fertility problems later on. You would know if you had a complication at the time. If all went well, it would not cause problems with getting pregnant or having a baby later on.