If you want to learn how to use a metronome you can pick up some ideas on You Tube. I posted one such tutorial video, with some comments here.
It's a bit longish. And it follows a traditional music notation pathway.
I find in teaching that the first thing a student needs to learn is start on the beat.
Then comes playing with the beat.
You learn how not to surge ahead or lag behind. When you have those two skills
mastered you can begin using the metronome in earnest. You play a tune or a section
of music with a steady pace. Then, you increase the speed just a little and play through again.
When I practice I usually set my numerical beats per minute to an increase of two when I do
this. Sometimes the increase seems minimal. Sometimes it seems like a big step up.
I haven't figured out why that is.
The metronome is a valuable tool. Make sure you get one you are going to enjoy using.