I would prefer a laptop (not a Chromebook) to a tablet, as you can store things such as personal documents and files on it, and they are generally easier to work on, because of the keyboard. This does depend on what you use your tech for, of course, and there is no one size fits all.
A tablet is better for carrying about - I liked my iPad when I was working full-time, but now that I'm not I haven't bothered to upgrade it. The laptop will do everything a tablet will do, as will a phone, but a tablet won't replace a laptop for everything.
People all have their favourites, but I use Apple for everything - phone, iPad and MacBook. They 'talk' to each other, so you can work on something on one device and it will pick it up on the others - same with photos and music. Apple customer service is good too. If you are upgrading all at once, I would recommend that you go into an Apple store, and one of their assistants will set everything up for you.
Your TV can probably be upgraded to SMART with either a fire stick or a Roku stick. They just plug into an HDMI port at the back of your TV (check that you have one) and will pick up a wide range of channels. You will need to subscribe to some of them (eg Netflix or Prime Video) but others are free, such as iPlayer and the other catch-up channels. They are well worth the money, in my opinion.
I'm not a fan of Alexa things, as in order to obey or answer your commands they have to listen to conversations in your home. A lot of people think that because they aren't criminals that this doesn't matter, but I'm not comfortable with it, and also, anything that is connected to the Internet can be hacked into, so it's another possible security risk. That's just me though - my mum and sister love their Alexas .
Music can be streamed free from Amazon prime if you have that, or you can get a Spotify account (or ask children/grandchildren if you can go on their Friends and Family list). As you have a lot of CDs, you can also save those to iTunes or Windows Music and play them through your laptop. You will need a separate CD drive for this, though, as most laptops are now internet only. They are cheap enough on eBay though - I think mine was about £20.
I think that covers all your questions, but shout if not? As I say, though, someone else may well give you very different advice - a lot of this is personal preference, and a lot depends on how you use your devices.