Well that would be a great decision! When you're ready to do travel full time, then that's an awesome step. As for your earnings, initially, you would have to get your own gears, and sponsor for your own travel, but trust me, if you do this with complete dedication, within a year or two, you will become a travel influencer. Various brands will start sponsoring you to travel and also the Tourism Departments of certain countries will invite you! Now if you wanna earn in the initial days of your travel life, then there are a lot of ways online! If you're good at something, like website development or design, photographer et all, then you have fiverr.com with you. You get paid for doing these! Check it out. The other way is to have a YouTube channel and start uploading your travel videos. You can approach people for a photoshoot, etc. Also you can create a website for yourself, link it with Google AdSense and earn. Before you quit your job, and take travel full time, make sure you have the required gear, sufficient money to sponsor your own travels. Cheers!
You can post your travel content on Youtube, Facebook, Instagram, Tripoto etc and get a good following first. After that you need to brand yourself good and other travel related companies to sponsor your travel and pay you for promoting their product. Also you can make your own travel site and earn by placing ads there and can start a small travel related company. Sponsored post on youtube and instagram can also give you a earning. There is a lot of ways. But first your need to grow your following and Brand.
It will take time. You must understand that earning money via travelling is difficult. But it is not impossible. You can choose to open a blogging website or YouTube channel and monetize them for earning money. However, you will need to attract a good amount of audience to your blog, channel or Instagram before you can earn money through brand promotions or sponsored trips. It is the popularity and engagement you have which will get you paid.