The lat/long values in your txt file don't form grids. If you need grids to cover certain area, Create Fishnet tool is good to use. Here is an exercise you can try to create a grid for the US:
- Run the Create Fishnet tool using the parameter values shown in the attachment. Your should get a line and a point outputs. These output will have "Unknown" coordinate systems.
- Run the Define Projection tool (Data Management toolbox - Projection toolset) on the line or point output and use "GCS_North_American_1983" or a desired projection as the Coordinate System. You should get the grid lines and points as shown in the attachment.
Hope that helps you to understand the Create Fishnet tool. You can then play with the parameters to get exactly what you neet.