I had a dna test done on my other child's father he is not the father of my 8yr old but he signed the birth certificate can his name be removed a my boyfriend signs his name on it

I will assume he thought he was father and it was not done due to fraud.

But the answer is maybe, some states in US allow, others will not. it will depend on where you live and perhaps if legal father (one on birth certificate agree) you will or should have a lawyer for this

Any question on law needs to include a general locale as laws vary by area. After 8 years it may be too late to challenge paternity.

And... Is your current boyfriend actually the father? If not, the only way to legally put him on the birth certificate is to find the biological father, have him release his parental rights and have your boyfriend adopt the child. That will probably require that you MARRY him first.

You can't just run around changing your child's legal parent when you switch men for yourself.

Was this question removed from another thread? Because it's sort of hard to decipher; the title suggests that OP is a male, however the question suggests that OP is the mother.

As Synnen indicates, changing the birth certificate is not the mechanism OP needs to adjust her domestic situation. That is one of the purposes for marriage and adoption.