To find and apply for a university in France online for a student visa on your own, without the help of any agency, you can follow these steps:

• Research universities in France: Start by researching universities in France that offer the course / subject you want to study. Websites like Campus France can provide complete information on universities in France, courses offered, and admission requirements.
• Check admission requirements: Once you have identified the colleges / universities, check their admission requirements to ensure you meet them. This may include academic qualifications, language tests, and other requirements and documents.
• Apply online: Most universities in France allow international students to apply online. You can visit the university’s website and follow the application process. After submission of application you will be intimated for a face to face short interview [usually 15 minutes]. After interview, the university issues an offer letter. After this step you can pay the course tuition fee either in partial or full. And then the Final acceptance letter + accommodations letter [ to be submitted to VFS ] are issued by the university.
• Obtain a student visa: Once you get above mentioned letters and other documents, you will need to apply for a student visa to study in France. You can apply for a student visa at the French embassy or consulate in your home country. The application process may require you to provide documents such as a passport, admission letter from the university, and proof of financial support.
• Apply in campus France by following the link inde.campusfrance.org. Here fill application excluding ITR and financial documents. Only academic related details need to be furnished here. Then again a face to face short interview by campus France manager will be required. Again that will be a quick 10-15 minutes video that will be only to assess your application so that the counsellor can check it further.
• After this meeting, campus France manager will issue a NOC for you. Along with that, a date will also be given from when you can start applying to VFS. Now go to a nearest VFS and submit your entire file with ITR and financial docs.
• Now the file goes to consulate. They take normally 10-15 days today generate results. Then your passport will get stamped with France visa that you had been waiting for. Now you are almost ready to fly.
• Plan your travel: Once your student visa is obtained, you can plan your study abroad journey to France. Before you arrive in France, it is important to secure accommodation. There are a number of options available, including student residences, private apartments, and homestays. Start your search early, as finding suitable accommodation can be competitive. Consider factors such as location, budget, and amenities when making your decision.
• Arrange for airport transfer, and explore the city and the university from internet before you arrive.
• Start applying early so there’s enough time to process everything and you don’t miss any deadlines.

Also, note that even though obtaining a French student visa without relying on an agency is possible, the process gets much smoother with the assistance from an agency.