Bitcoin newbie - Bitcoin advice

Hello Everyone.

I'm Jack. I'm a total newbie to Bitcoin so please bare with me If I say anything which is incorrect.

I've been using Bitcoin for about 3 weeks now and managed to earn a total of 0.01443865 BTC which is not bad saying that I have earned all this using free methods.

(I'm trying to reach a target of 0.50 BTC to try this website selling products, If all goes well I can see me using bitcoins even more.)

I have some concerns with Bitcoin and I would love to hear your advice/comments.

With bitcoin being decentralised what will happen when services like online wallets/blockchain are taken offline or removed as a service.

Also with hackers trying very hard to obtain bitcoins do you think companies will stop taking bitcoins as payments?

Thanks,

Jack