Welcome!

It's a perfect "fitness bike" and with basic maintenance it can deliver many miles and hours of happiness.

Seems that the seat post is looking in the wrong direction, so probably you should set it up correctly before placing a new saddle.

Regarding the fork, if I would be in your shoes, I won't spend a cent on fixing it. If you really need a suspension fork, you can find affordable alternatives, but if you don't just leave it as it is right now. Not sure if it has coils or elastomers inside. But both usually got stuck inside the forks with the time, and unless it's a good fork, it does not worth it to fix it.

Enjoy it!

Oh, and 53 it's not old at all... 50s are the new 40s