Yes you are correct, it is not advisable to sell everything you have and invest it to bitcoin specially if you have little experience woth bitcoin and cryptocurrency. I suggest you start a little first, start woth an amount you are okay to lose and once you get the hang of it you can add more.
Agree, do not put all your savings in cryptocurrency as we all know, market is very unpredictable and you never know what will happen next. The best thing would be to invest money in cryptocurrency that you can afford to loose just in case if it will not be successful towards the end. Once your investment would gain, you may start to get your capital and leave the profit behind and let it stay for good.