Moving to Berlin in March / Looking for my long term home / English and Polish speaking / 39 years of age

Hi I am looking for a good but cheap property to live in, I will be transferring to Berlin on 1st March. My office is based in Franklinstraße so ideally the place would be within public transport distance.
I am clean and independent and have lived on my own in the UK for over 7 years. I have 2 grown up children that will likely visit at a later stage but again they would only visit so a 1 bedroom apartment or studio apartment would be ample and comfortable.
I am very clean and have been since I first lived on my own in 2003, I like to keep things in order and looked after. I am 39 so my partying days are not with me anymore, I do like to socialize but prefer a quieter neighborhood and life.
In the future I would like to have somewhere to park a vehicle, but this isn't a priority for me at the moment. Ideally some where with good internet connection as I work in IT and would like to be able to work remote during pandemic times.

My company is happy to supply a reference for the time I have been working with them which has been for a number of years.

My max price for rent is 850euros warm rent, if you have furniture that would be great but I do have my own in Poland and England.

I am Polish and English so have all the legal requirements to be living in the EU.