You would need to play in college as the teams would need recent film on how you played in college. ... If you don't play in college, there is basically no way to walk onto a NFL team as they usually don't hold public tryouts.

Is there open tryouts for NFL?

The NFL notified its teams that it is lifting the prohibition of free-agent tryouts. Effective immediately, teams are no longer required to have an open roster spot to hold a free-agent tryout, according to the memo sent to teams and obtained by USA TODAY Sports.

Is it possible to walk into a NFL team?

Anyone is allowed to enter the NFL draft, as long as they have graduated high school. If you don't play in college, continue training hard and consider becoming a walk-on.