When people told me "Having a child will change your life forever" I'd smile politely and say" Oh I hope so!"... If I only knew LOL
There are things you can do. First, eliminate places for him to "get into ".
Toddler-proof your home. Put away the fragile things, and the things you can't loose. Small toys should go on high shelves, things like crayons and craft things should only be used under your supervision, and put away afterward. They make toilet seat "locks" and cabinet locks, .. go buy them today :-)
Place ALL cleaning supplies and medicines ( even vitamins,supplements and OTC medicines) in a high cupboard LOCKED with a cabinet lock. After my daughter learned to open those we used combination locks.
Get rid of the highchair and get your son a booster seat. Hopefully when your second son is ready to transition from eating in the bouncer ( or car-seat, or whatever you are using to feed him in now), your older boy will be less enthusiastic about climbing it. If not.. fold it up and put it behind locked doors until meal time.
Close and lock all doors. We had a hook and eye system on the outside of our room and the bathroom for years.
Place a bolt lock high up on your front door, and install those battery operated alarms on your sliding/screen doors, so you'll know if he "escapes" If you have a pool, be sure it's securely fenced! I was a paramedic,a nd you'd ne horrified to realize how many p\toddlers die in backyard pools.
Travel with a baby gate or two.. they work wonders at other people's houses. Also ask that they "toddler-proof" their homes while you are there. You shouldn't have to watch hom like a hawk at Gramma's house)
As far as spending time with family/friends at functions, they'll have to follow you around as you follow your son if they want to talk to you. Invite them to do that... don't feel odd about it. are there events where hiring a babysitter would be better for you?
Are you a single mom? If not, insist your husband take a "shift" at family functions. You deserve a little adult time just like he does.
I actually put my daughter on a "leash" when she was a toddler. It was a belt with her own fanny pack, which she loved, and it had a D-ring and a tether you could clip on to it. We used it in Disneyland, it worked so well that after that we used it at large social gatherings. It allowed me to know when she was "on the move" if I became distracted. It also gave me another way to hold onto her when she refused to hold my hand.
Your son's behavior sounds normal to me, although more active than I was used to.
Try to foresee and prevent.. and ask for help when you need it! And as other moms have said, ... This too shall pass