If you travel in a straight line in space & keep going & going & going, would one eventually reach the end of space?

Rather in the same way that you can travel round and round the Earth without ever stopping, the Universe is believed to be finite but unbounded.  It is a difficult concept for the human mind, for so long used to dealing in 3 dimensions, that space curves in all directions - sometimes this is represented as a doughnut, but it is a 4 dimensional doughnut. Therefore, it is possible to surmise that if you could travel forever in one direction, you would end up where you started. But it's a difficult concept to get your head around.  There are also other problems, related to the fact that the Universe is also expanding at the same time.

Space has no end:)

Eventually you will die , but wont find end of space

If there is an end of space, but hey, you'll need to be over billions year olds to go that far and more

Oh yes why not but what will do after reaching the end point of the space? Would you like to put a flag over there ha ha haha .... Amazing question!

What we know for sure is that the universe is expanding at a phenomenal rate so unless you were going faster that that you could never reach the end. Likely its impossible to travel this fast.
For the sake of argument lets say you are though, what exactly would happen is up for debate and by no means certain, most theorists would as stated above suggest that you would end up where you started and that the universe loops back on itself.

These answers are all fascinating and I really can't do any better.  Just for the record, I think if you traveled long enough (one human lifetime would probably not be long enough) you would get back to where you started from, because the theory is that everything is circular.  You could not actually travel in a straight line.  But I wonder what Steven Hawking would say about it.

It's super hard to grasp in our minds but space continues forever and forever and forever. Us as humans can't imagine "forever" because we always think that there has to be an ending point, there has to be an ending point. But in space, there isn't one. You can easily confuse yourself by thinking about that for five minutes straight. Same with how I imagine that we live in Heaven forever --- it twists all up in my mind unitl I'm so confounded I can't think to the point where the imagination first started. :)

I'll will tell you from experience even with a straight line of sight you would eventually end up back where you started with enough time. Because all humans have one leg shorter the other and by nature/design you would turn to the left or right as you walked,drove,flew, unless you had a instrument to correct your direction of travel as you went like a fixed positon object in your view that you could adjust your  travel by. Now since all things in the solar system/galaxies are set in circular patterns you would eventually circle around anyway/anywhere you traveled.think about it you may travel straight from point to point but it all is in a circle. This is my story and I am sticking to it.

Only if you could accelerate faster than light

Space is finite. People have absolutely no comprehension of how the expansion of space actually works. It's just a plane that warps and twists, distorting distances and figures that we know of.