Can I cut off or use wart remover to remove scar tissue from a healed cut at the base of my penis I nicked myself a few times while shaving my genital area. After the small cuts healed, scar tissue grew and they look like skin tags?

This . This could be razor bumps (pseudofolliculitis), skin tags, warts, molluscum, a scar, or several other possibilities. I think you should probably see a dermatologist to confirm the diagnosis and to discuss treatment options. I hope that helps.
This . This sounds like a distinctly bad idea to me. I agree with the advise of seeing a dermatologist.
Please don't. Since you have penile scarring from episodes of shaving your genitalia- i would like to encourage you to consider stopping this practice. There isn't a medical reason to shave your penis. Please do not cut your penis any further or place caustic chemicals on it. Please see a dermatologist for care.