You can get the tutorial for composing a good CV online. There are many open resources from where you can learn, this. Now there are several colleges/ universities which releases notifications for internships you can apply for it also for example, the summer internship program is going on in KIIT. Now if you want to go for companies then as per my advice it will be best to apply via online platforms such as LinkedIN, Naukri, Internshala. Now as per my opinnion Internshala is the easiest website, you have to enter your details and with the details the cv will be automatically made, and you  have to apply for internships and then you have to apply and if shortlisted then you will get notified. So you can surely visit that as well as the other and find for internship opennings.

I hope this answer helps. All the very best for your future endeavors!