Do I need to quit apps and also do I need to shut down my Mac or just put it to sleep?

Simple answer: yes and no.

For apps: shutting them down when not being used does return RAM memory back and reduces the amount of CPU usage. This is more critical when your Mac has limited RAM and/or CPU power.

For the Mac itself: There has always been two camps around this topic. Personally, I turn off my Mac at the end of the day. Then power it back up in the morning, or when I first need to use it. The other camp suggests that you leave it on, and then, use the "Power Nap" mode to reduce its consumption when not being actively used.

The reason I don't fall into the latter camp is twofold:

1. Some Macs are a bit "finicky" waking up from sleep. You will find posts here related to that issue.
2. Even this method requires that you periodically power down the Mac as over time you will notice it will be running slower for a number of reasons (not necessarily bad ones.)

I'm in the school with Tesserex in shutting down my Mac at night. That clears out temporary system and application swap and cache files. Some of those files can get damaged/corrupted and create performance problems, some subtle.

You can delete local snapshots from the different volumes with Disk Utility.

FWIW I shut down my Macs if needed to run updates. That's all. They run 24/7 otherwise.

I'm in the camp that turns it off when not actively using it.

FWIW, I'm in the camp that never turns off my iMac or puts it to sleep. I just have the display turn off after some time of inactivity. I'm on and off my iMac 24/7 so it is just easier to leave it on.

If you want to keep on then do not use sleep. This can cause issues with attached hardware. Just have your display turn off.