Is it possible to install home assistent and serviio on the same raspberry pi.
Serviio is a media server
Dont know what serviio is but on first glace it seems to be an application that can be installed on linux.
2 approaches do come to my mind (IF THE APPLICATION works headless without HDMI):
- Install Proxmox as a host and install HAOS as guest OS and a generic linux (debian?) Machine and install serviio manually
- Create a Docker/APP(Addon) Container and use it as a container. -> if you dont know where to start, dont bother
bottom line: it can work, but its gonna need some time to work.
I dont want to offtopic this: it would help to know why you especially need this application and how you use it and maybe if no alternative works for you to be honest. Your question provides too few context.
You can use Emby or Plex from GitHub - alexbelgium/hassio-addons: My homeassistant addons ยท GitHub who has a ton of addons/apps which can be easily be used that might be a (better) substitution for you.
where is emby or plex installed then? I use serviio mediaplayer because it plays subtitles directly on my old philips tv from 2012. On my tv i can access network and there i see the serviio. And played out of the box subtiles on my tv. What I seem to remember is that Plex couldn't play subtitles that way.
It is installed on where you hit "install" on your Home assistant.
Read more about apps/addons first:
thats a bummer, so your solution is hyper specific but legit.
So you either (From hardest to easiest):
(Needs knowledge and you need to know what to do -> im not recommending options 1+2, because it can be super pesky BUT they are imo the most elegant solution ):
Option 1: create your own Addon Tutorial: Making your first app | Home Assistant Developer Docs
Option 2: Run HA via Proxmox and make another Linux Server that uses serviio
(Needs some knowledge, BUT its a standard setup and works with a little bit effort and the Pi Imager AND there are plenty of youtube videos of it and since you have serviio as a server on your Pi, its gonna be dead easy for you i guess BUT not as elegant like options 1+2 ):
Option 3a: Take that Pi (i hope thats a Pi3 or even 4), Install Something like Kodi/XBMC/LibreELEC/OSMC (Any Media OS) and use it as a DIY Media Box to view Videos via SMB (Network Share). Files can be stored on Homeassistant theoretically and be made accessible with SMB.
Option 3b: Take somethink like a Apple TV / Fire TV stick or whatever Android Media Box and stream from SMB (Network Share) with VLC Player
Files can be stored on Homeassistant theoretically and be made accessible with SMB.
Lazy Mode (super ghetto mode) :
Option 4: Stay like it is and "hope" your TV dies someday and your Pi survives so you can replace it with a modern TV and VLC Player or whatever.
If i were you I would try to use the Pi, connect it via HDMI and AT LEAST try option 3a OR 3b, because even if your TV dies, you can use the SMB Share for your new TV, so you have 80% done for the future and made it future proof.
What variant of Pi and How much ram does it have is the FIRST question. HA has min system requirement that includes Pi4 with 2G ram.
...But if you're running something else as WELL, then minspec is HA minspec + Other thing minspec.
How big is the Pi. 
Oh youre right, i reread the first entry and I THOUGHT he has already HA installed and needs a solution for his TV...........but since he has a Pi and using it as media box.....well....the options are useless i guess since i thought he already has HA installed on a device already....