This guide will let you know how to Run/Move faster in Modern Warfare. Go through the guide and follow the steps to do so.
First, you have to make sure that you are using the tactical button layout preset in the game’s settings.

With this option, your right analog stick will work as the crouch function for your controller. And you can run and slide without taking the handoff of your analog stick.
You will need to start the game and sprint your character; while doing it, you have to sprint again, which will unlock the tactical sprint, as shown in the image below.

When you drop the gun and stop sprinting at full speed, you have to crouch and see that your character goes into a slide. You can start the slide by clicking down on your right analog stick while sprinting forward.

After that, click on the slide animation again before the slide ends to cancel the slide, and you will get back sprinting again. You will need to repeat the steps sprinting, slide and then cancel. When you get up from the second slide, then you will unlock another tactical sprint function. It will increase your mobility.
