The sim800l that is not 5v tolerant. powering it from 5v in arduino

dear friends am looking at interfacing my project with the sim800l module the one that is not 5v tolerant ...i was looking at using resistors to bring down the 5v to around 4v .... has anyone tried this ? any suggestions on current variable .... any guide is much appreciated... using a lipo battery is not an option ....but using the 5v telerant version can be an option if my above proposal doesnt work out but still powering it from my power source will be my second option but am yet to design it and also i cant use the buck converters since every dollar counts here...TIA

One way or another you will have to make a power supply for the SIM800L.
Depending - it may require 800mA, which is basically out of an Arduino's capability.

That won't work for anything with variable current draw, and the Arduino cannot be used as a power supply.

this saved me a big "research"

No, 2A is the requirement. Its designed to be powered from a single LiPo cell as in a mobile phone (all GSM chips are designed for this power source). Something like 4V at 3A or more is the kind of power supply to use if not using LiPo.

Sounds like a good candidate for a 'power bank'.

" Power requirements is probably the most common issue with the SIM800L. This board draws a maximum of 2 A with an input voltage of 3.7 V to 4.2 V. This means you must not connect its pins directly to a 5 V Arduino! It doesn't even run on 3.3 V. However, its TX and RX pins are 5V tolerant.

Some YouTube videos power their modules from the Arduino UNO's power pins which really doesn't work for me. When on USB port, the Arduino's 5V pin can supply a maximum of 450 mA and when on its DC Jack, about 800 mA."

I have had my sim800L baseboard running fine straight from the arduino 3.3v today to check out the fm radio function.

Start the phone function/s and let us know how that goes.