Newbie trying to program a microcontroller

Hello! New to the forum and new to coding!

Recently got an Arduino Uno to try and program some ATtiny13's to control a signal latching relay. Attached is the schematic I will be using.

Basically what I want to do is when I press N/O switch, I want the LED to turn on and activate the coil in the relay to stay on until I press the switch again. I would also like a momentary function, by holding the switch will activate everything and then when I let go, it goes back off, and vice versa.

I figure there's plenty of on/off guides, but I don't know how to go about the momentary function. Can anyone point me in the right direction?

Thank you!

This is a very simple application of maintaining a state. On detecting a button press, you set the state variable if it is currently unset. You unset it if it is currently set. The state variable is used to control the relay. The button may need debouncing.

You can model all that on the uno before even considering the attiny13.
The relay probably needs a transistor to drive it. The led probably does not, but use a current limiting resistor.

It is unusual to use 2 gpio pins to control a relay coil.