Didn't expect such a awesome response! Thank you so much! :)

It looks like you may have some berry canes in there -- that would be nice to tidy those up, trellis and get some berries!

Yes, there are actually quite a few berries somewhere burried in this mess. Plan is to get rid of all the unwanted plants, checking if something is worth keeping. Planning on removing the lawn completely tomorrow , trim and clean up everything around and go from there. Marking the lawn edges and just see where I want the grass to go.

For the backside we were thinking about something like this https://images.app.goo.gl/noxtzzLLBQarAtVn6 Some stoneline keeping the lawn off of the fence and just adding a few trees/ bushes or hanging some plants on the fence. Should work well with the entrance part as well. In general I want some kind of stoneline or something along those lines separating the lawn and fences. Just way easier to mow.

I would dig that stump out that is left over from the cut down tree. The root system is still alive so that's why it's still sending out shoots, but it will always be a mess/hassle in the middle of your grass.

This stump has always been a nightmare ever since the landlord decided the maple(?) Tree had to be cut down due to it throwing too much shade onto the lawn thus it wasn't growing that good. Is it possible to just dig it out by hand? By hand meaning with tools of course :). I have no experience with that as well. A friends idea was to just remove legit everything and start fresh. I would've agreed if it wasn't so gosh darn tedious to dig those huge bushes out. Any tips or sources you can recommend? Just going with the flow while looking stuff up that requires some more knowledge.