I have a lot of seeds, mostly flower ones. Should I plant them in fall or wait till spring? Will they be ok or are they too old to grow?
While it may depend on the type of flowers you have, I would say for most it would be ok to plant them in spring.
How do I germinate cheap seeds?
Here is an article that you may find helpful: https://www.gardeningknowhow.com/garden-how-to/seeds/cheap-seed-starting-how-to-germinate-seeds-at-home.htm
The scattering of seeds from one place to another.
Scattering seeds is simply another term for sowing seeds. Generally, you place some seeds (such as wildflower seeds) in your hand and lightly 'scatter' them throughout the planting bed. This method usually does not require soil coverage, though you can lightly rake over the area to cover the seeds if desired. Scattered seeds will eventually germinate (given water and light), filling the area with beautiful flowers. Note: many of the seeds used in wildflower mixes are from self-seeding varieties.
When do I start vegetables from seed indoors?
This article should help with that: https://www.gardeningknowhow.com/edible/vegetables/vgen/growing-vegetables-with-seeds.htm
I would start them about 6 to 8 weeks before last frost date,this should give u time to harden them off some,before going to garden, if tomato plants,may want to put in larger container, when they get 5 leaves or more, good luck
Do packet seeds die?
Yes, there is a lifespan to seeds. As time passes, their ability to germinate decreases. But, if properly stored, most seeds are viable for years. This article will explain more:
https://www.gardeningknowhow.com/garden-how-to/seeds/planting-old-seeds.htm
Over the years I have planted seeds indoors so I can have a nice potted plant area in my backyard. Every single time I've tried to do this (both flowers and vegetables) they sprout, grow a few inches, then die off. What am I doing wrong?
This is called damping off. This article will help you correct it:
https://www.gardeningknowhow.com/garden-how-to/seeds/what-is-damping-off.htm
When I plant small seeds, I can't separate them as they keep bunging up.
Smaller seeds are most often scattered directly onto the planting area rather than "planted" as most traditional seeds are. They are also only lightly covered with soil, if at all.