Why does a 2001 blazer with a 4.3liter hesitate when pressing the accelerator?

I have a cash pit, I mean 97 Jacket 4.3L with 260k miles. As of late it began to have some faltering in it. First saw it while on the turnpike, the vehicle appeared to stagger a little and the RPMs would shudder 100RPMs or something like that. Presently it is encountering wavering while speeding up regularly in first or second. It keeps on shuddering at high paces also. Searching for guidance on what to have a go at dealing with first.