My mother leaves in Colombia and I want her to come visit me for six months! what is the right visa?

A visitor visa is a B-2. She needs to apply for it in Columbia. She'll need to prove sufficient ties to Columbia. Any support you offer her demonstrates that you love her but does not help her chances for a B-2. She has to demonstrate sufficient reason to a consular officer when she applies that she will return to Columbia. The ties must be compelling. Merely owning a home or having money in a Columbian bank are not compelling- she can sell the home and withdraw the money. Getting a visa can be difficult, so be patient.