IN WHICH MEDIUMS CAN AN FIR BE INSTITUED UNDER THE NEW LAW AND UNDER WHICH SECTION?

Let's start- 

First of all, we have to know about the FIR. 

FIR - First information report 
          it is only instituted in cognizable offence.
          (Cognizable offence means an offence for which police officer may, in accordance   with the first schedule or under any other law for the time being in force, arrest without warrant).
In short, we can say that FIR can be instituted for serious offences.

FIR is not substantial piece of evidence. its only use to contradict or corroborate the matter. 
(Shambhu Dass vs. state of Assam, AIR 2010 SC 33000).

As we know, FIR instituted under section 154 of code of criminal procedure.
what it said- 
Information in cognizable cases.
offence against woman must be written by woman police station.
copy of information as recorded the information shall be given forthwith, free of cost, to the informant.
If police refused to take FIR informant can send that information to superintendent of police (SP) By post office under section 154(3).

Now The FIR instituted under section 173 of  Bharatiya Nagarik Suraksha Sanhita 2023.
all are same as it is mentioned in section 154 of code of criminal procedure.
but in section 173 now FIR will be instituted by electronic communication, it shall be taken on record by him (police) on being signed within 3 days by the persons giving it.

https://youtu.be/cQli9DvZsnQ

  173. (1) Every information relating to the commission of a cognizable offence, irrespective of the area where the offence is committed, may be given orally or by electronic communication to an officer in charge of a police station, and if given.
(i) orally, it shall be reduced to writing by him or under his direction and be read over to the informant; and every such information, whether given in writing or reduced to writing as aforesaid, shall be signed by the person giving it.
(ii) by electronic communication, it shall be taken on record by him on being signed within three days by the person giving it and the substance thereof shall be entered in a book to be kept by such officer in such form as the State Government may by rules prescribe in this behalf

Provided that- 

 if the information is given by the woman against whom an offence under section 64, section 65, section 66, section 67, section 68, section 69, section 70, section 71, section 74, section 75, section 76, section 77, section 78, section 79 or section 124 of the Bharatiya Nyaya Sanhita, 2023 is alleged to have been committed or attempted, then such information shall be recorded, by a woman police officer or any woman officer:

Provided further that- 

(a) in the event that the person against whom an offence under section 64, section 65, section 66, section 67, section 68, section 69, section 70, section 71, section 74, section 75, section 76, section 77, section 78, section 79 or section 124 of the Bharatiya Nyaya Sanhita, 2023 is alleged to have been committed or attempted, is temporarily or permanently mentally or physically disabled, then such information shall be recorded by a police officer, at the residence of the person seeking to report such offence or at a convenient place of such person's choice, in the presence of an interpreter or a special educator, as the case may be-

(b) the recording of such information shall be videographed.

(c) the police officer shall get the statement of the person recorded by a Magistrate under clause (a) of sub-section (6) of section 183 as soon as possible.

(2) A copy of the information as recorded under sub-section (1) shall be given forthwith, free of cost, to the informant or the victim.

(3) Without prejudice to the provisions contained in section 175, on receipt of information relating to the commission of any cognizable offence, which is made punishable for three years or more but less than seven years, the officer in charge of the police station may with the prior permission from an officer not below the rank of Deputy Superintendent of Police, considering the nature and gravity of the offence-

(i) proceed to conduct preliminary enquiry to ascertain whether there exists a prima facie case for proceeding in the matter within a period of fourteen days or

(ii) proceed with investigation when there exists a prima facie case.

(4) Any person aggrieved by a refusal on the part of an officer in charge of a police station to record the information referred to in sub-section (1), may send the substance of such information, in writing and by post, to the Superintendent of Police concerned who, if satisfied that such information discloses the commission of a cognizable offence, shall either investigate the case himself or direct an investigation to be made by any police officer subordinate to him, in the manner provided by this Sanhita, and such officer shall have all the powers of an officer in charge of the police station in relation to that offence failing which such aggrieved person may make an application to the Magistrate.

note- if anyone wants to Learn about all sections in short video they can visit BOOK OF INDIAN LAW YOU TUBE CHANEL.

www.bookofindianlaw.com