Some food for thought and context to help you to understand the parties and party system in the USA:
So here's another view of the ideological basis of US political parties and the perpetual evolution they undergo is pursuit of popularity and power. This 'mini lecture' takes an historical view of this process which is useful for contextual understandings of the two main parties in the run up to the presidential election 2020 (like all these vids, have a pen/paper/laptop to hand for noting!):
And here's some insights into the stances of the two parties in the run-up to the 2020 election - again great for supporting your notes. Indeed, you NEED to be noting a bunch of the info from these!!