I was approved for HELOC, the bank sent me a check book, I think the check has routing and checking number, is it possible to enter the checking and routing number on the college website to pay for tuition, instead of writing a check to myself and use my bank’s routing and checking number to pay tuition?
Probably. Make sure the HELOC account doesn’t have a hold period.
@twoinanddone what is a hold period for HELOC ? have tried to google 
Some banks clear checks nightly, others hold the check for the time allowed by law (which is a lot longer than you’d think under Dodd Frank). Just ask your bank how long they take to clear the check. Sometimes for large checks, they do hold them just to make sure there isn’t fraud.
I’m not sure if the HELOC money has been moved to a checking account or if every time you present a check it make a ‘loan’ from your line of credit. It might take a day or two to have the loan processed.