I have left you a review. As you will see, there were numerous points in this game where you could have won the game, as well as played stronger moves. I give a great deal of suggestions in the chat. I will now copy and paste some of those suggestions here. Just in case any other new players might be reading this but choose to skip the review.
This game was using Chinese Rules, where a single stone is worth 1 point. Under Japanese rules, these extra stones wouldn’t have mattered as much. If you are unsure of how Japanese and Chinese rules differ, you can refer to this thread which should make it crystal clear on how they differ and how points are calculated in each.
You can easily learn to recognize situations like this by practicing Tsumego Problems. They train your mind to “read” the board. You can learn more about them, and several other newbie friendly resources, in this thread.
The actual post that mentions Tsumego is linked in that thread. Here is a direct link to the Tsumego thread. The best Tsumego Collection to start with is Walken’s version of Cho Chikun’s Encyclopedia of Life & Death. You can find those here and read why they are the best version on OGS here.