After all G.I benefits are used what type of funding is available to get continue on to get a master’s degree?

In addition to the steps LTC Eugene Chu mentioned (especially joining the National Guard*), check with your state's Veterans Affairs Office to see if there are state programs/scholarships available for veterans residing in that state.

There are many resources to find scholarships for veterans*, you just need to do some creative internet searching.

If you have a disability rating of 10% or more from the VA, you might be eligible for VR&E if a Vocational Rehabilitation Counselor determines you need it.
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* Many states will fully fund a bachelor or graduate degree at a state university if you belong to the state's National Guard.
* https://www.bestcolleges.com/resources/military-veteran-scholarships/
* https://www.dvs.virginia.gov/wp-content/uploads/2021/01/Veteran-Scholarships-and-Grants-1-19-21.pdf

Veteran Readiness and Employment (Chapter 31), formerly Vocational Rehabilitation maybe:
https://www.va.gov/careers-employment/vocational-rehabilitation/

I faced the same situation. In my case, as long as I was enrolled in an approved university or college and pursuing a higher level degree . . . no problem, I got the rest of my months. That was my experience.

Hello SPC Jasmine Paredes, Have you used the Pell Grant?

Some Universities have the Yellow Ribbon program available, asked the Veterans department for info...