One thing I would advise you is to always download the wallet directly from developer's website. Ignore other platforms like Google Play or App store as you might get a fake wallet by mistake. Regarding the explorers, I (as many others here) personally prefer
https://blockchair.com/.
Additionally to what others have said, I strong suggest that you buy a hardware wallet if you are thinking about owing more than a thousand dollars and you wanna hold your bitcoins in long term.
Yeah hardware wallet is a convenient way to store crypto and is worth investing into, but another good option for a very long term hodl is paper wallet too. It costs nothing and if done properly it is very safe so it isa good option for someone that can't afford hardware wallet right from the beginning.
Hmm. Those are quite interesting(and very amateur, to say the least) questions to ask from someone that has been here since 2017..
When you check his post history, you realize why he is asking this "newbish" question. Despite him being member of the forum since 2017 he has been mostly active in altcoin section. In the end, it's never late to focus on bitcoin.