Welcome to OG @Going2fast . So for the giveaways you can just go to the free seeds and free clones thread and offer them up. The rules are up to you. The only protocol is “free”, otherwise you can choose USA only, World Wide, been on the site a certain amount of time or whatever you fell you want. I will link that thread below.
As for sending seeds, there are many ways to save them from being crushed by the postal system rollers. Coin flips with hose washer, corrugated plastic with supports, 3d printed seed pucks. All are easily searched here. If you have specific questions feel free to tag me or pm me, I send out a fair number of seeds so know a bit about getting them there safe.