I have rendered a few PNG images in Blender and trying to combine them into a video. Is there any tool that can help me achieve my goal?
There is a tool called FFmpeg perfectly made for your use case. FFmpeg allows you to create a video from images with different video codecs and options, you can use the following command to convert PNG images into MP4 video with an H264 video codec.
And here is the solution if you missed adding keyframes to the video.
How to set a particular frame rate while combining a bunch of images into a video using FFmpeg?
FFmpeg provides -r or -framerate options to specify the output video frame. If you want to create a video with 60 FPS you can specify -r 60 in your FFmpeg command.