I cant live with this weirdness anymore please help me out

Hello i am a 19 years old male in university. Please take some time and read my post i really need that. I have these thoughts since when i was 10. They started with not stepping on the lines and soon the thought captured all my brain tw my mom and dad had several serious health problems which i think had a bad influence on my thoughts cause i started to think that they were gonna die.
Everything i do i always thought about them diying even in happy moments there are these unwanted pictures in my head related woth their death.
Whenever i think about this i start to avoid the thoughts and FIGHT them with other images or i re-do something : if im drinking water and this thought came i drink once more while trying to replace the image and the thought in my head.
There is this feeling that particular things might cause damage to my parent like using the left hand to do something, leaving something unsymmetrical. I really cant live my life i always re-do these rituals i cant even drink a cup of water. I feel like if i dont replace the thoughts the bad ones will come true and something bad will happen to my parents. I cant even write dad or mom in the last sentence bad and those words shouldnt be in the same sentence orelse i feel unconfortable and start doing the rituals. Please help me i cant live with this anymore ease help me out thank you all so much.

I really suggest that you go to a psychiatrist for an evaluation or at least a therapist to get started, if that's a possibility for you. If you have insurance, OCD treatment should be covered. I promise you that life can get so much better.
I was plagued by ocd my whole life and like you, spend most of my waking moments visualizing horrific things or ritualizing to avoid them. My life is different now on medication. I am a completely different, happier person. Medication and/or therapy (so I hear) can help.....
Good luck!