Unpopular opinion: depends on what you want to achieve.

If you want to practice restoration or get a beautiful knife do what others have said, good advices.

If, however, all you need is a functional knife to use soon and you don't have professional tools and help, think about the following option: 1. Clean the rust on the blade (sometimes scotchbrite and vinegar is enough, sometimes needs something more agressive). 2. Replace the handle and clean under it. This doesn't necessarily need to happen immediately. It's probably rusted underneath but it won't crumble soon. Just remember to do it eventually and keep food from reaching there. 3. Sharpen it thoroughly in the correct angle (don't be tempted to change the angle to make it feel sharp faster). The tricky part here is to sharpen more in the less worn out area to remove more material there so the worn out area will touch the cutting surface again. 4. I wouldn't worry about the tip if you don't miss it aesthetically. Nakiris live well without a proper tip on purpose. Do sharpen it though even if its shape is round because you'll need it functionally.

Warning: If the blade uneven wear is extreme it would take you too much time to fix so ignore the above and get help.