What Camera/Lenses should I Get?

I see you are new...

The numbers that you have quoted for your lenses are the minimum focus distances, not the focal lengths. The focal lengths will be written in large letters on the body of the lens, e.g. 18-55mm. The focal length range is also marked underneath the zoom ring. However, from the focus distances that you have quoted I think that you probably have an 18-55mm IS kit lens, which is a good general purpose lens, and a 75-300mm which is a rather poor telephoto lens.

As others have said, your camera body is still pretty good and you won't gain a lot from upgrading. I used to have a DSLR with that sensor and you should be fine up to ISO 1600. For low light you will gain much more by getting one or more lenses with larger maximum apertures (smaller f/ number). The Canon 50mm f/1.8 is very reasonably priced and is a good portrait lens, or you could get a Sigma 17-50mm f/2.8 to replace your kit lens. Another option would be to buy an external flash with a rotating head that can be twisted upwards to bounce off the ceiling. That would give far better quality flash shots than the built in flash.

Astrophotography is rather a specialised area and may also require a new lens. Get advice on the astrophotography forum. Macro photography with a DSLR will probably also require a special macro lens although if you just want to experiment you can get macro filters that screw onto the front of your existing lenses.

If you are disappointed with the image quality from your 75-300mm lens (if that is what you have) then the Canon 55-250mm STM is a good replacement.

Tripod screw sizes are standard and a tripod with a protruding screw fitting will fit any camera with a tripod screw mount.

Your camera is not up to date to present standards but it is still OK-ish if you have good lenses on it.

I reckon you have 18-55 mm and 75-300 mm. There is a plethora of 18-55 mm from Canon but you would have the one with IS that came as kit for that lens. Personally I find 55 mm too short for my use of a zoom lens but your preferences could be different.

All dSLR manufacturers have good bodies nowadays, even Canon has caught up with the competition. Although any Nikon camera in your price range would be better than Canon offerings (that still have a handicap from smaller sensor) I would stay with Canon since you are accustomed to it.

The current body would be Canon T7i that is above your budget. Any cameras up to Canon T5i that was launched back in 2013 would be essentially the same as your camera so not worth to buy them.

I would rather buy a better lens. Depending on your uses it may be a faster standard zoom like Sigma 17-50 f/2.8 (but you will gain only 2/3 stops at wide end while at long end you will have 2 full stops of advantage), a better telephoto like 55-250 mm IS STM. For macro you may look at Tamron 90 mm f/2.8.

As you can see you cannot fit all within your budget so you may want to prioritize. I would put macro lens on the last place since you are not sure if you want to do a lot of macro. Based on your post I would say that a faster standard zoom and a good flash would be optimal use of the budget. Take care that the flash to have rotating head (tilt and swivel) and to be compatible with eTTL. Metz or Canon would be the safest options. Cheapest would be the Chinese flashes that may have some issues. All of my friends that bought such type of flashes had some issues with them from minor to severe. Usually the issues were not in the first year.

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Victor
Bucuresti, Romania

Keep the camera. Learn photography. Buy a flash and learn how to use it. Shoot lots and cirtique the photos to the max and you will become very good. Then you will know what lens to get next. Buy used to save money. However if you NEED to buy a lens get the 50mm f1.8. Good lens, very useful focal length, awesome max aperture. A good lens to learn on and one you will keep with you for years.

I have to say I'm with Redreing1 here. The gear you have is perfectly adequate for general photography. While the camera may be 7 years old, if you do want to update, decide what style of photography you want to concentrate on and then choose a new lens.

If possible buy a good used lens as this will keep your outlay low.

I have just bought a Canon 1000d with the same kit lenses you have, at least I'm guessing that they are the same given the details you provided, and while the non-stabilised 70-300 lens isn't a world beater it can still produce some nice imagery, even handheld with a bit of care.

See here for what I mean.

And of course you can always update the body as well if there is something currently missing that you really need.

Good luck in your choices for the future.

Instead of a camera, I would suggest a much cheaper alternative - a good book on the very basics of photography. The level of your ignorance is overwhelming.