(Apols, my A key is a bit dodgy and only works half the time)
You don't have to leave him to cry if you don't want to.
I used to grab a quick shower before XP left for work in the morning.
I would let DS crawl around in the bathroom when I was having a poo (this is such a personal preference - some people will say "I couldn't imagine anything worse than having them in there with me!" and some will say "I couldn't bear to leave them crying while I use the toilet!")
It's perfectly OK to start things and leave them half done - as soon as the washing machine cycle ends I will pull out all the washing into a basket and as long as I don't leave it too long (ie overnight) it stays fresh smelling for a lot longer than it would have if left in the machine. So I will hang as much up as I can, then go off and chase DS up the stairs/play with him for a bit/change his nappy etc etc and come back to it later.
Washing up I will only half fill the sink (so if I have to stop I don't wste so much wter) and tend to do it when he is having a snack or something in his highchair so I know he can't go anywhere.
I have got a ring sling - a ring or pouch sling or other crrier you cn use on your hip is excellent, otherwise, I just got used to doing things one handed. The thing about the sling is as you get more confident/they get older, you can scoot it round onto your back nd be able to do more, I even cook with DS on my back now occsionally. (Just be extra careful to avoid their feet being able to kick things) At 8 months DS was often happy to sit in his high chair with a suction type toy and watch me do things, or in his buggy outside watching me hang out the washing.
If you do need to go out of view for a minute, keep talking to him to ressure him, if he is getting bored watching you, try singing songs or put the radio on and do silly dance. As he gets older he can "help" by putting clothes in the wshing machine, "sweeping" the floor etc. It will probably take twice as long but it's good for them to learn early, and fun for him (and funny to watch)
And I do lso think that they do get bored nd cry sometimes, but it's ok, I am now a single mum and DS hs to go in the playpen sometimes (such as if I m getting something out of the oven, or if he is wanting to ply with something dangerous when I m trying to do something importnt) nd if what I m doing is taking too long he does sometimes cry - I just talk to him in a bright voice or sing loudly at him or make silly noises to mke him laugh, and sometimes I am too tired and I do just ignore him, but he is older now and can understand more, and it's never for too long at a time. You need to find your own level of what you are comfortable with