dying pine tree
The tree looks like it may be a Virginia pine but we cannot say for sure. The tree is too large for the container. The tree is most likely be pot bound and is affecting the root system. We also see some trunk damage and there is nothing that you can do for this.
Here are some thoughts. The tree looks like it is declining. You can take it out of the pot and do some root pruning and repot into a larger container. Make sure the container has holes for good drainage. Do this on a warm day. Leave the top growth as is and see what comes back in the spring. Monitor the plant for additional symptoms.
You may also want to look into bonsai and this is a specialty area. You can look online for bonsai clubs in the area for possible advice on the subject and to see if this is an option. This is not our area of expertise.