i just registered for a 5 week i.t course that starts in June and ends in august and the fee is $13000. The venue is at pennyslavania, U.S.A
Now the school ( sap academy) said they would email me a letter of invite which i would take to the embassy to show that i have fully registered for the sap course and paid fully. I asked for the form I 20 but they said they dont give that, i understand the form I 20 is only given to students who intend to go to the U.S for undergraduate and graduate courses.
Now i have paid fully, but what are the chances of me getting the usa visa?, also what type of visa should i apply for?, should it be visiting visa or student visa?

you made a mistake per se. It is alwayz advisable to pay 40-6y0 percent of the fee cuz ou are not sure whether visa will be given to you or not cuz paing the whole fee does not mean they must give u.

Plan B is to ask the skool if the money is refundable, good luck, i hope u get it

I agree. Paying fully for a course that you may not be able attend is not too wise. There is no guarantee that you will get a visa even by paying the entire fee for the course.  See what their refund policy is and if you can get your money back. Not sure what can be taught to you any way to cost that much money. Most people that attend those kinds of courses here have it paid for by their company.

they are not likely to give you the visa. just ask for your refund.
the fact that you were desperately quick to pay $13,000 for a 6 week computer course that may have been available in your own country is a huge red flag. How do you prove to the consular officer that you are not willing to do anything to immigrate to the US?
$13,000 is more than most of the consular officers can boast of in 6 months.

Get your refund and try another method.

It is their policy that you pay in full before you are given a booking. And their refund policy is that i will be refunded 100% in a case where i am not able to attend the 5 week course.
Also it is not that i am desperate but they require full payment also the sap course i want to do is not done anywhere in africa apart from south africa; and south africa uses the old software version to teach.
So what do you think i should take to the embassy that will increase my chances of getting the usa visa

well take the letter of admission to the embassy and if refused, ask the skool to write the. Above all, be prayerful

Actually there is no letter of admission and no form I 20 just a letter of invite from SAP America that will inform the US Consulate that i have registered for training with SAP America during fixed period of time.

Also can someone tell me which type of visa i should apply for? B1 VISA?

You should have gone the Visitor Visa way, then when u are there u apply for the 5weeks course.
Now the US Consulate will be suspicious of you and the 5weeks course because they know there are many IT courses
there in Nigeria, so you took the hard way to come to the US. But then, everything is a trial in life so you never know
where your bread is buttered. Just ask for your money before the deadline so that you could get everything back,

$13,000 (13k dollars is alot of money man).

For intending F1 student, they have alot of huddles you know, even though they have full scholarship and everything for their 4years course.
Not to talk of a 5weeks. I don't think they give F1 20 unless your are going for an undergraduate or postgraduate schooling.

For every impending non immigrants (students) must have F1 20 from your school, Admission letter etc.

Maybe visitor's visa.
Your intended course, SAP is a great course. We did the Enterprise in class and am still lost .
So keep hope high okay.

any other recommendation on which type of visa i should apply for?

Dude

I think you should get your money back and DO not apply for any Visa at this time. There is just too much confusion in your way, you have to have your ducks in a row.

Abeg any body don go embassy recently for F1 student visa to Lamar University in State of Texas for fall semester? abeg If there is anybody like that I need a roomate. Its a nice 2 bedroom apartment very close to school, secure and very cozy. U can hit me up on oagbroko@lamar.edu