Since you are a beginner, an evergreen (juniper, pine etc) will not be a good tree if you insist on having an indoor tree. Those are outdoor trees. Same with trident and Japanese maples and pretty much most of the species you are going to encounter. Yes there is one guy in the whole world that has managed to keep a procumbens nana juniper alive inside for 20+ years, under an intensive and extensive light set up and seasonal routine that will be way more than your $100 budget. It really isnt about what you prefer, it is about what you are willing and able to provide for the tree to live. You will have a very hard time keeping a juniper, pine, maple etc alive inside.
So for an indoor tree, as suggested, ficus is a good choice for a beginner. However, if you really want them to thrive and not just barely survive, you will need to provide supplemental lighting. Just putting on a window sill will not work long term and trees kept in this manner almost invariably have other problems at some point or another.
Yes all trees need to be repotted regularly because their roots will continue to grow and eventually get pot bound. This needs to be dealt with periodically. The time between repottings depends on several factors: age of the tree, size of the tree, size of the pot, how fast it is growing, and species of the tree among others. Trees never stop growing, unless they are dead and they will always need pruning, repotting, root work etc.
If you are not able or are not willing to provide what the tree needs in terms of environment (nutrients, light, water, soil, pot, dormancy, outside), and things it needs for its care, you might want to rethink your interest in the hobby. I dont mean to sound harsh, but there is a lot involved and it takes commitment to follow through or you will be in for a lot of frustration and disappointment and you wont enjoy the hobby.
Good luck
