It's all in your head. From day to day, the way you choose to take on your activities is how far you will go in life. There are 24 hours in a day, and your mentality will either propel you upstream, or it can have you struggling to paddle against the current.
Get the laziness and lack of effort out of your head.
To put things in perspective, here is a personal example. I'm currently taking human anatomy which is typically considered a more difficult course. Every Monday, I have a three-hour lab pertaining to what is in the textbook. It's not a hands-on lab, it's essentially an additional three-hour lecture. Now I know the thought of a professor lecturing on bones, muscles, and organs for three hours is not very thrilling, but it's my attitude and work ethic that will make or break the experience.
I have one of two options to going about it. Option one: bitch and moan, have no interest or desire to be there and put in no effort, OR option two: be attentive, be interested to learn, stay positive, and put in the best effort that I possibly can. If I weigh my two possibilities, what exactly am I going to achieve from being negative and not even making an attempt to succeed? On the other hand, if I'm enthusiastic to be there, then I will have the energy to try my hardest and most likely succeed. After all, this class is what my future revolves around, so why not take advantage of the given moments that will help me excel?
Your future is dependent on your present. The decisions you make every day could affect what is yet to come. If you wake up every morning with a head full of negative thoughts, it will carry through the whole day making you feel unmotivated, uninterested, and you won't be working to your full potential. If you wake up at the beginning of each day with nothing but positivity on your mind, your day will be 1000% different. Your day will benefit you due to motivation, determination, a goal in mind, and you will most definitely go above and beyond in terms of work ethic.
Your attitude and mentality are crucial parts of a well-oiled machine that's en route to the finish line. It's like putting diesel fuel in an Audi versus putting in premium fuel. Treat it well, and you'll be revving the engine to the destination. Mistreat it, and there will be lots of complications on the road.
Stop getting stuck in your head. Stop saying I can't and start saying I know I can. Stop thinking about the what-ifs and take risks. Stop doing the bare minimum and start doing the most. Success is mentally driven, and if you have a goal in mind — STOP MESSING AROUND AND CHASE THAT DAMN DREAM.
It's not gonna chase itself, and it all starts with you.