Paying for Utility bills will not improve your credit score or help build credit since the Utility bills are not reported to the credit agencies unless you fall behind on the Utility Bill payments and then it can hurt your credit score.
Just make sure to pay your Utility bills and never let the Utility Bills get sent to collection agencies otherwise it will destroy your credit score.
Only loans and credit cards etc can help build credit scores up so long as you pay the loans and credit card bills on time and never default on them.
You can get a secured credit card through Capital One or other credit card companies by putting up a deposit which is used as your credit limit and then use the credit card like you would any other credit card.
You pay the credit card bill on time for what you've used and then it will help build your credit score and rating up as long as you keep the credit card in good standing.
Then you can get approved for other loans and credit cards once your credit score has gone up.
Secured Credit Cards can help rebuild a persons credit rating and score too.